Precursors and uses for cis and cigs photovoltaics

ABSTRACT

Methods for photovoltaic absorber materials for uses including solar cells. The methods include depositing onto a substrate an ink comprising one or more compounds having the formula M B (ER) 3  wherein M B  is In, Ga or Al, E is S or Se, and R is selected from alkyl, aryl, heteroaryl, alkenyl, amido, and silyl, and heating the substrate.

BACKGROUND

The development of photovoltaic devices such as solar cells is importantfor providing a renewable source of energy and many other uses. Thedemand for power is ever-rising as the human population increases. Inmany geographic areas, solar cells may be the only way to meet thedemand for power. The total energy from solar light impinging on theearth for one hour is about 4×10²⁰ joules. It has been estimated thatone hour of total solar energy is as much energy as is used worldwidefor an entire year. Thus, billions of square meters of efficient solarcell devices will be needed.

Photovoltaic devices are made by a variety of processes in which layersof semiconducting material are created on a substrate. Layers ofadditional materials are used to protect the photovoltaic semiconductorlayers and to conduct electrical energy out of the device. Thus, theusefulness of an optoelectronic or solar cell product is in generallimited by the nature and quality of the photovoltaic layers.

One way to produce a solar cell product involves depositing a thin,light-absorbing, solid layer of the material copper indium galliumdiselenide, known as “CIGS,” on a substrate. A solar cell having a thinfilm CIGS layer can provide low to moderate efficiency for conversion ofsunlight to electricity. The CIGS layer can be made by processing atrelatively high temperatures several elemental sources containing theatoms needed for CIGS. In general, CIGS materials are complex, havingmany possible solid phases.

For example, some methods for solar cells are disclosed in U.S. Pat.Nos. 5,441,897, 5,976,614, 6,518,086, 5,436,204, 5,981,868, 7,179,677,7,259,322, U.S. Patent Publication No. 2009/0280598, and PCTInternational Application Publication Nos. WO2008057119 andWO2008063190.

The CIGS elemental sources must be formed or deposited, eitherindividually or as a mixture, in a thin, uniform layer on the substrate.For example, deposition of the CIGS sources can be done as aco-deposition, or as a multistep deposition. The difficulties with theseapproaches include lack of uniformity of the CIGS layers, such as theappearance of different solid phases, imperfections in crystallineparticles, voids, cracks, and other defects in the layers.

A significant problem is the inability in general to precisely controlthe stoichiometric ratios of the metal atoms in the layers. Manysemiconductor and optoelectronic applications are highly dependent onthe ratios of certain metal atoms in the material. Without directcontrol over those stoichiometric ratios, processes to makesemiconductor and optoelectronic materials are often less efficient andless successful in achieving desired compositions and properties. Forexample, no molecule is currently known that can be used alone, withoutother compounds, to readily prepare a layer from which CIGS materials ofany arbitrary stoichiometry can be made. Compounds or compositions thatcan fulfill this goal have long been needed.

A further difficulty is the need to heat the substrate to hightemperatures to finish the film. This can cause unwanted defects due torapid chemical or physical transformation of the layers. Hightemperatures may also limit the nature of the substrate that can beused. For example, it is desirable to make thin film photovoltaic layerson a flexible substrate such as a polymer or plastic that can be formedinto a roll for processing and installation on a building or outdoorstructure. Polymer substrates may not be compatible with the hightemperatures needed to process the semiconductor layers. Preparing thinfilm photovoltaic layers on a flexible substrate is an important goalfor providing renewable solar energy and developing new generations ofelectro-optical products.

Moreover, methods for large scale manufacturing of CIGS and related thinfilm solar cells can be difficult because of the chemical processesinvolved. In general, large scale processes for solar cells areunpredictable because of the difficulty in controlling numerous chemicaland physical parameters involved in forming an absorber layer ofsuitable quality on a substrate, as well as forming the other layersrequired to make an efficient solar cell and provide electricalconductivity.

What is needed are compounds, compositions and processes to producematerials for photovoltaic layers, especially thin film layers for solarcell devices and other products.

BRIEF SUMMARY

This invention relates to compounds and compositions used to preparesemiconductor and optoelectronic materials and devices including thinfilm and band gap materials. This invention provides a range ofcompounds, compositions, materials and methods directed ultimatelytoward photovoltaic applications and other semiconductor materials, aswell as devices and systems for energy conversion, including solarcells. In particular, this invention relates to novel processes,compounds and materials for preparing semiconductor materials.

This invention provides compounds, compositions, materials and methodsfor preparing semiconductors and materials, as well as optoelectronicdevices and photovoltaic layers. Among other things, this disclosureprovides precursor molecules and compositions for making and usingsemiconductors such as for photovoltaic layers, solar cells and otheruses.

The compounds and compositions of this disclosure are stable andadvantageously allow control of the stoichiometry of the atoms in thesemiconductors, particularly the metal atoms.

In various embodiments of this invention, chemically and physicallyuniform semiconductor layers can be prepared with the polymericprecursor compounds described herein.

In further embodiments, solar cells and other products can be made inprocesses operating at relatively low temperatures with the compoundsand compositions of this disclosure.

The polymeric precursor compounds and compositions of this disclosurecan provide enhanced processability for solar cell production, and theability to be processed on a variety of substrates including polymers atrelatively low temperatures.

The advantages provided by the compounds, compositions, and materials ofthis invention in making photovoltaic layers and other semiconductorsand devices are generally obtained regardless of the morphology orarchitecture of the semiconductors or devices.

In some embodiments, this invention includes a compound comprisingrepeating units {M^(A)(ER)(ER)} and {M^(B)(ER)(ER)}, wherein each M^(A)is Cu, each M^(B) is In or Ga, each E is S, Se, or Te, and each R isindependently selected, for each occurrence, from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands.The compound may be a CIGS, CIS or CGS precursor compound.

A compound may have the empirical formulaCu_(x)(In_(1-y)Ga_(y))_(v)((S_(1-z)Se_(z))R)_(w), wherein x is from 0.5to 1.5, y is from 0 to 1, z is from 0 to 1, v is from 0.5 to 1.5, w isfrom 2 to 6, and R represents R groups, of which there are w in number,which are independently selected from alkyl, aryl, heteroaryl, alkenyl,amido, silyl, and inorganic and organic ligands. A compound may bedeficient in Cu or enriched in Cu. A compound may be an inorganicpolymer or coordination polymer, or linear, branched, cyclic, or amixture of any of the foregoing. A compound can be an oil at atemperature below about 100° C. A compound may be an alternatingcopolymer, a block copolymer, or a random copolymer.

A compound of this disclosure may have the formula (AB)_(n), wherein Ais the repeat unit {M^(A)(ER)(ER)}, B is the repeat unit{M^(B)(ER)(ER)}, n is two or more, or n is three or more, and R isindependently selected, for each occurrence, from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands. Acompound may have any one of the formulas: (RE)₂-BB(AB)_(n),(RE)₂-B(AB)_(n)B, (RE)₂-B(AB)_(n)B(AB)_(m), (RE)₂-(BA)_(n)BB,(RE)₂-B(BA)_(n)B, (RE)₂-(BA)_(n)B(BA)_(m)B, ^(cyclic)(AB)_(n),^(cyclic)(BA)_(n), (RE)₂-(BB)(AABB)_(n), (RE)₂-(BB)(AABB)(AB)_(m),(RE)₂-(B)(AABB)_(n)(B)(AB)_(m), (RE)₂-[B(AB)_(n)]⁻, (RE)₂-[(BA)_(n)B]⁻,

(RE)₂-BB(AB¹)_(n)(AB²)_(m), (RE)₂-BB(AB¹)_(n)(AB²)_(m)(AB¹)_(p), and amixture thereof, wherein A is the repeat unit {M^(A)(ER)(ER)}, B is therepeat unit {M^(B)(ER)(ER)}, n is one or more, or n is two or more, or nis three or more, m is one or more, and p is one or more.

This disclosure further provides an ink comprising one or more of thecompounds. An ink may be a solution of the compounds in an organiccarrier. An ink may contain a dopant or alkali dopant. An ink cancontain an additional indium-containing compound, an additionalgallium-containing compound, or a molybdenum-containing compound. An inkmay contain one or more components selected from the group of asurfactant, a dispersant, an emulsifier, an anti-foaming agent, a dryer,a filler, a resin binder, a thickener, a viscosity modifier, ananti-oxidant, a flow agent, a plasticizer, a conductivity agent, acrystallization promoter, an extender, a film conditioner, an adhesionpromoter, and a dye.

In further aspects, this invention includes methods for making aprecursor compound by a) providing monomer compounds M^(B1)(ER)₃,M^(B2)(ER)₃, and M^(A)(ER); and b) contacting the monomer compounds;wherein M^(B1) is In, M^(B2) is Ga, M^(A) is Cu, each E is S, Se, or Te,and R is independently selected, for each occurrence, from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands.M^(B1) and M^(B2) may both be In, or both Ga. In certain embodiments,the monomer compounds can be contacted in a process of depositing,spraying, coating, or printing.

This disclosure includes a compound made by a process comprisingreacting monomers M^(B1)(ER)₃, M^(B2)(ER)₃, and M^(A)(ER), whereinM^(B1) is In, M^(B2) is Ga, M^(A) is Cu, each E is S, Se, or Te, and Ris independently selected, for each occurrence, from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands. Acompound may have three or more repeating units {M^(B)(ER)(ER)}. Incertain embodiments, a compound may have three or more repeating units{M^(A)(ER)(ER)}.

Embodiments of this invention may further provide an article comprisingone or more compounds or inks deposited onto a substrate. The depositingmay be done by spraying, spray coating, spray deposition, spraypyrolysis, printing, screen printing, inkjet printing, aerosol jetprinting, ink printing, jet printing, stamp/pad printing, transferprinting, pad printing, flexographic printing, gravure printing, contactprinting, reverse printing, thermal printing, lithography,electrophotographic printing, electrodepositing, electroplating,electroless plating, bath deposition, coating, wet coating, spincoating, knife coating, roller coating, rod coating, slot die coating,meyerbar coating, lip direct coating, capillary coating, liquiddeposition, solution deposition, layer-by-layer deposition, spincasting, solution casting, and combinations of any of the forgoing.

The substrate can be selected from the group of a semiconductor, a dopedsemiconductor, silicon, gallium arsenide, insulators, glass, molybdenumglass, silicon dioxide, titanium dioxide, zinc oxide, silicon nitride, ametal, a metal foil, molybdenum, aluminum, beryllium, cadmium, cerium,chromium, cobalt, copper, gallium, gold, lead, manganese, molybdenum,nickel, palladium, platinum, rhenium, rhodium, silver, stainless steel,steel, iron, strontium, tin, titanium, tungsten, zinc, zirconium, ametal alloy, a metal silicide, a metal carbide, a polymer, a plastic, aconductive polymer, a copolymer, a polymer blend, a polyethyleneterephthalate, a polycarbonate, a polyester, a polyester film, a mylar,a polyvinyl fluoride, polyvinylidene fluoride, a polyethylene, apolyetherimide, a polyethersulfone, a polyetherketone, a polyimide, apolyvinylchloride, an acrylonitrile butadiene styrene polymer, asilicone, an epoxy, paper, coated paper, and combinations of any of theforgoing. The substrate may be shaped, including a tube, a cylinder, aroller, a rod, a pin, a shaft, a plane, a plate, a blade, a vane, acurved surface or a spheroid.

This invention discloses methods for making an article by (a) providingone or more compounds or inks; (b) providing a substrate; and (c)depositing the compounds or inks onto the substrate. Step (c) can berepeated. The method may further include heating the substrate at atemperature of from about 100° C. to about 400° C. to convert thecompounds or inks to a material. The method may further include heatingthe substrate at a temperature of from about 100° C. to about 400° C. toconvert the compounds or inks to a material, followed by repeating step(c). In certain embodiments, the method can include annealing thematerial by heating the substrate at a temperature of from about 300° C.to about 650° C. The method can also include heating the substrate at atemperature of from about 100° C. to about 400° C. to convert thecompounds or inks to a material, and annealing the material by heatingthe substrate at a temperature of from about 300° C. to about 650° C.The method may further include heating the substrate at a temperature offrom about 100° C. to about 400° C. to convert the compounds or inks toa material, depositing the compounds or inks onto the substrate, andannealing the material by heating the substrate at a temperature of fromabout 300° C. to about 650° C. Further steps of the method may include(d) heating the substrate at a temperature of from about 100° C. toabout 400° C. to convert the compounds or inks to a material; (e)depositing the compounds or inks onto the substrate; (f) repeating steps(d) and (e); and (g) annealing the material by heating the substrate ata temperature of from about 300° C. to about 650° C. Additional stepscan include (d) heating the substrate at a temperature of from about100° C. to about 400° C. to convert the compounds or inks to a material;(e) annealing the material by heating the substrate at a temperature offrom about 300° C. to about 650° C.; and (f) repeating steps (c), (d)and (e).

In certain embodiments, the method may include an optional step ofselenization or sulfurization, either before, during or after any stepof heating or annealing.

In some aspects, this invention includes a material having the empiricalformula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), wherein x is from0.5 to 1.5, y is from 0 to 1, and z is from 0 to 1, v is from 0.5 to1.5, and w is from 1.5 to 2.5.

Further embodiments include methods for making a material by (a)providing one or more compounds or inks; (b) providing a substrate; (c)depositing the compounds or inks onto the substrate; and (d) heating thesubstrate at a temperature of from about 20° C. to about 650° C. in aninert atmosphere, thereby producing a material having a thickness offrom 0.001 to 100 micrometers. The substrate may be heated at atemperature of from about 100° C. to about 550° C., or from about 200°C. to about 400° C.

In some embodiments, this invention provides a thin film material madeby a process comprising, (a) providing one or more compounds or inks;(b) providing a substrate; (c) depositing the compounds or inks onto thesubstrate; and (d) heating the substrate at a temperature of from about20° C. to about 650° C. in an inert atmosphere, thereby producing a thinfilm material having a thickness of from 0.001 to 100 micrometers.

This invention includes a photovoltaic absorber having the empiricalformula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), wherein x is from0.5 to 1.5, y is from 0 to 1, and z is from 0 to 1, v is from 0.5 to1.5, and w is from 1.5 to 2.5.

In further aspects, this disclosure includes methods for making aphotovoltaic absorber layer on a substrate by (a) providing one or morecompounds or inks; (b) providing a substrate; (c) depositing thecompounds or inks onto the substrate; and (d) heating the substrate at atemperature of from about 100° C. to about 650° C. in an inertatmosphere, thereby producing a photovoltaic absorber layer having athickness of from 0.001 to 100 micrometers.

In some embodiments, this invention includes a photovoltaic device madewith a compound or ink described above. In certain aspects, thisinvention contemplates methods for providing electrical power using aphotovoltaic device to convert light into electrical energy.

This brief summary, taken along with the detailed description of theinvention, as well as the figures, the appended examples and claims, asa whole, encompass the disclosure of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an embodiment of a polymeric precursor compound (MPP). Asshown in FIG. 1, the structure of the compound can be represented by theformula (RE)₂BABABB, wherein A is the repeat unit {M^(A)(ER)₂}, B is therepeat unit {M^(B)(ER)₂}, E is a chalcogen, and R is a functional group.

FIG. 2 shows an embodiment of a polymeric precursor compound (MPP). Asshown in FIG. 2, the structure of the compound can be represented by theformula (RE)₂BABABBABAB, wherein A is the repeat unit {M^(A)(ER)₂}, B isthe repeat unit {M^(B)(ER)₂}, E is a chalcogen, and R is a functionalgroup.

FIG. 3 shows an embodiment of a polymeric precursor compound (MPP). Asshown in FIG. 3, the structure of the compound can be represented by theformula (RE)₂BA(BA)BB, wherein A is the repeat unit {M^(A)(ER)₂}, B isthe repeat unit {M^(B)(ER)₂}, E is a chalcogen, and R is a functionalgroup.

FIG. 4 shows an embodiment of a polymeric precursor compound (MPP). Asshown in FIG. 4, the structure of the compound can be represented by theformula (RE)₂BA(BA)_(n)B(BA)_(m)B, wherein A is the repeat unit{M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is a chalcogen, and Ris a functional group.

FIG. 5 shows an embodiment of a polymeric precursor compound (MPP). Asshown in FIG. 5, the structure of the compound can be represented by theformula ^(cyclic)(BA)₄, wherein A is the repeat unit {M^(A)(ER)₂}, B isthe repeat unit {M^(B)(ER)₂}, E is a chalcogen, and R is a functionalgroup.

FIG. 6: Schematic representation of embodiments of this invention inwhich polymeric precursors and ink compositions are deposited ontoparticular substrates by methods including spraying, coating, andprinting, and are used to make semiconductor and optoelectronicmaterials and devices, as well as energy conversion systems.

FIG. 7: Schematic representation of a solar cell embodiment of thisinvention.

FIG. 8 shows the transition of a polymeric precursor embodiment (MPP) ofthis invention into a material as determined by thermogravimetricanalysis. As shown in FIG. 8, the molecular structure of the precursorcompound is represented by the repeat unit formula {Cu(Se^(sec)Bu)₄In}.The transition of the precursor compound into the material CuInSe₂ wascompleted at a temperature of about 230° C.

FIG. 9 shows the transition of a polymeric precursor embodiment (MPP) ofthis invention into a material as determined by thermogravimetricanalysis. As shown in FIG. 9, the molecular structure of the precursorcompound is represented by the repeat unit formula {Cu(Se^(sec)Bu)₄Ga}.The transition of the precursor compound into the material CuGaSe₂ wascompleted at a temperature of about 240° C.

FIG. 10 shows the transition of a polymeric precursor embodiment (MPP)of this invention into a material as determined by thermogravimetricanalysis. As shown in FIG. 10, the molecular structure of the precursorcompound is represented by the repeat unit formula{Cu(Se^(t)Bu)(Se^(n)Bu)In(Se^(n)Bu)₂}. The transition of the precursorcompound into the material CuInSe₂ was completed at a temperature ofabout 245° C.

FIG. 11 shows the transition of a polymeric precursor embodiment (MPP)of this invention into a material as determined by thermogravimetricanalysis. As shown in FIG. 11, the molecular structure of the precursorcompound is represented by the repeat unit formula {Cu(Se^(t)Bu)₄Ga}.The transition of the precursor compound into the material CuGaSe₂ wascompleted at a temperature of about 175° C.

FIG. 12 shows the transition of a polymeric precursor embodiment (MPP)of this invention into a material as determined by thermogravimetricanalysis. As shown in FIG. 12, the molecular structure of the precursorcompound is represented by the repeat unit formula{Cu(S^(t)Bu)₄(In_(0.75)Ga_(0.25))}. The transition of the precursorcompound into the material CuIn_(0.75)Ga_(0.25)S₂ was completed at atemperature of about 235° C.

FIG. 13 shows the transition of a polymeric precursor embodiment (MPP)of this invention into a material as determined by thermogravimetricanalysis. As shown in FIG. 13, the molecular structure of the precursorcompound is represented by the repeat unit formula{Cu(S^(t)Bu)₄(In_(0.9)Ga_(0.1))}. The transition of the precursorcompound into the material CuIn_(0.9)Ga_(0.1)S₂ was completed at atemperature of about 230° C.

FIG. 14 shows the transition of a polymeric precursor embodiment (MPP)of this invention into a material as determined by thermogravimetricanalysis. As shown in FIG. 14, the molecular structure of the precursorcompound is represented by the repeat unit formula{Cu(Se^(t)Bu)(Se^(n)Bu)(In_(0.70)Ga_(0.30))(Se^(n)Bu)₂}. The transitionof the precursor compound into the material CuIn_(0.7)Ga_(0.3)Se₂ wascompleted at a temperature of about 245° C.

FIG. 15 shows the transition of a polymeric precursor embodiment (MPP)of this invention into a material as determined by thermogravimetricanalysis. As shown in FIG. 15, the molecular structure of the precursorcompound is represented by the repeat unit formula{Cu(Se^(t)Bu)(Se^(n)Bu)(In_(0.75)Ga_(0.25))(Se^(n)Bu)₂}. The transitionof the precursor compound into the material CuIn_(0.75)Ga_(0.25)Se₂ wascompleted at a temperature of about 240° C.

FIG. 16 shows the transition of a polymeric precursor embodiment (MPP)of this invention into a material as determined by thermogravimetricanalysis. As shown in FIG. 16, the molecular structure of the precursorcompound is represented by the repeat unit formula{Cu_(0.85)(Se^(t)Bu)_(0.85)(Se^(n)Bu)In_(0.70)Ga_(0.30)(Se^(n)Bu)₂}. Thetransition of the precursor compound into the materialCu_(0.85)In_(0.7)Ga_(0.3)Se₂ was completed at a temperature of about230° C.

FIG. 17 shows results of methods for stoichiometric control of thecomposition of a polymeric precursor embodiment (MPP) of this invention.The x-axis refers to the weight percent of a particular atom, either Cu,In or Ga, in the monomer compounds used to prepare the polymericprecursor. The y-axis refers to the weight percent of a particular atomin the precursor compounds as synthesized. The straight line correlationobserved in FIG. 17 shows that the stoichiometry of the polymericprecursor can be precisely controlled with the quantities of themonomers used to make the polymeric precursors.

FIG. 18 shows the X-ray diffraction pattern of a CIGS material made withthe polymeric precursor {(0.85 Cu)(Se^(t)Bu)(Se^(n)Bu)(0.7 In,0.3Ga)(Se^(n)Bu)₂}. The X-ray diffraction pattern of FIG. 18 shows thepresence of a single crystalline CIGS phase, namely a tetragonalchalcopyrite phase.

FIG. 19 shows an analysis by X-ray diffraction of the structure of thecrystalline phase of CIGS materials made with various polymericprecursors having a range of percent indium, as shown on the x-axis,from about 30% to about 90%, where percent indium is 100*In/(In+Ga). Theresults in FIG. 19 show that the degree of incorporation of indium andgallium in the crystals of CIGS materials can be detected by therelative position of the 2-theta-(112) peak of the X-ray diffractionpattern. As shown in FIG. 19, for crystals of CIGS materials, a linearcorrelation was found between the percent indium of the precursor andthe position of the 2-theta-(112) peak, showing that the stoichiometryof a CIGS material can be precisely controlled by the structure of thepolymeric precursor used for its preparation.

FIG. 20 shows an analysis by Dynamic Light Scattering of the molecularweight of three polymeric precursors of this disclosure. The polymericprecursors were made from the chain-forming reaction of monomers of A,providing repeat units {M^(A)(ER)₂}, and monomers of B, providing repeatunits {M^(B)(ER)₂}. Polymeric precursors 1, 2 and 3 had estimatedmolecular weights of 17 kDa, 87 kDa, and 59 kDa, respectively.

DETAILED DESCRIPTION

This disclosure provides a range of novel polymeric compounds,compositions, materials and methods for semiconductor and optoelectronicmaterials and devices including thin film photovoltaics and varioussemiconductor band gap materials.

Among other advantages, the polymeric compounds, compositions, materialsand methods of this invention can provide a precursor compound formaking semiconductor and optoelectronic materials, including CIS andCIGS absorber layers for solar cells and other devices. In someembodiments, the optoelectronic source precursor compounds of thisinvention can be used alone, without other compounds, to prepare a layerfrom which CIS, CIGS and other materials can be made. Polymericprecursor compounds may also be used in a mixture with additionalcompounds to control stoichiometry of a layer or material.

In general, the ability to select a predetermined stoichiometry inadvance means that the stoichiometry is controllable.

This invention provides polymeric compounds and compositions forphotovoltaic applications, as well as devices and systems for energyconversion, including solar cells.

The polymeric compounds and compositions of this disclosure includepolymeric precursor compounds and polymeric precursors for materials forpreparing novel semiconductor and photovoltaic materials, films, andproducts. Among other advantages, this disclosure provides stablepolymeric precursor compounds for making and using layered materials andphotovoltaics, such as for solar cells and other uses.

A photovoltaic absorber material of this disclosure can retain theprecise stoichiometry of the precursor used to make the absorbermaterial.

Polymeric precursors can advantageously form a thin, uniform film. Insome embodiments, a polymeric precursor is an oil that can be processedand deposited in a uniform layer on a substrate. This invention providespolymeric precursors that can be used neat to make a thin film, or canbe processed in an ink composition for deposition on a substrate. Thepolymeric precursors of this invention can have superior processabilityto form a thin film for making photovoltaic absorber layers and solarcells.

In certain aspects, this invention provides polymeric precursorcompounds having enhanced solubility in organic solvents. The solubilityof a polymeric precursor makes it advantageous for preparingphotovoltaic materials using any one of various processes that requiredeposition of the precursor on a substrate, such as for making thin filmsolar cells. A polymeric precursor may have enhanced solubility in oneor more carriers for preparing an ink to be deposited on a substrate.

In further embodiments, this invention provides a range of polymericprecursor compounds for which the solubility can advantageously becontrolled and selectively varied. In these embodiments, the solubilityof a polymeric precursor can be enhanced by variation of the nature andmolecular size and weight of one or more organic ligands attached to thecompound. The control of polymeric precursor solubility can allow thepreparation of inks having controlled viscosity, for example, amongother properties.

In general, the structure and properties of the polymeric compounds,compositions, and materials of this invention provide advantages inmaking photovoltaic layers, semiconductors, and devices regardless ofthe morphology, architecture, or manner of fabrication of thesemiconductors or devices.

The polymeric precursor compounds of this invention are desirable forpreparing semiconductor materials and compositions. A polymericprecursor may have a chain structure containing two or more differentmetal atoms which may be bound to each other through interactions orbridges with one or more chalcogen atoms of chalcogen-containingmoieties.

With this structure, when a polymeric precursor is used in a processsuch as deposition, coating or printing on a substrate or surface, aswell as processes involving annealing, sintering, thermal pyrolysis, andother semiconductor manufacturing processes, use of the polymericprecursors can enhance the formation of a semiconductor and itsproperties.

The polymeric precursor compounds and compositions of this invention mayadvantageously be used in processes for solar cells that avoidadditional sulfurization or selenization steps.

For example, the use of a polymeric precursor in semiconductormanufacturing processes can enhance the formation of M-E-M′ bonding,such as is required for chalcogen-containing semiconductor compounds andmaterials, wherein M is an atom of one of Groups 3 to 12, M′ is an atomof Group 13, and E is a chalcogen.

In some embodiments, a polymeric precursor compound contains achalcogenide bridge having the formula M^(A)(E)M^(A), M^(B)(E)M^(B) orM^(A)(E)M^(B).

A polymeric precursor compound may advantageously contain linkagesbetween atoms, where the linkages are desirably found in a material ofinterest, such as a CIGS material, which material can be made from thepolymeric precursor, or a combination of polymeric precursors.

The polymeric precursor compounds of this disclosure are stable andadvantageously allow control of the stoichiometry, structure, and ratiosof the atoms in a semiconductor material or layer, in particular, themetal atoms.

Using polymeric precursor compounds in any particular semiconductormanufacturing process, the stoichiometry of the metal atoms can bedetermined and controlled. The structure of a polymeric precursor maycontain a number of different metal atoms. Polymeric precursors havingdifferent metal atoms, and different numbers of metal atoms can becontacted in precise amounts to control the metal atom stoichiometry ina semiconductor manufacturing process. For processes operating atrelatively low temperatures, such as certain printing, spraying, anddeposition methods, the polymeric precursor compounds can maintain thedesired stoichiometry. As compared to processes involving multiplesources for semiconductor preparation, the polymeric precursors of thisinvention can provide enhanced control of the uniformity and propertiesof a semiconductor material.

These advantageous features allow enhanced control over the structure ofa semiconductor material made with the polymeric precursor compounds ofthis invention. The polymeric precursors of this disclosure are superiorbuilding blocks for semiconductor materials because they may provideatomic-level control of semiconductor structure.

The polymeric precursor compounds, compositions and methods of thisdisclosure may allow direct and precise control of the stoichiometricratios of metal atoms. For example, in some embodiments, a polymericprecursor can be used alone, without other compounds, to readily preparea layer from which CIGS materials of any arbitrary stoichiometry can bemade.

In certain aspects, polymeric precursor compounds can be used to formnanoparticles that can be used in various methods to preparesemiconductor materials. Embodiments of this invention may furtherprovide processes using nanoparticles made from polymeric precursors toenhance the formation and properties of a semiconductor material.

In aspects of this invention, chemically and physically uniformsemiconductor layers can be prepared with polymeric precursor compounds.

In further embodiments, solar cells and other products can be made inprocesses operating at relatively low temperatures using the polymericprecursor compounds and compositions of this disclosure.

The polymeric precursors of this disclosure are useful to prepare inksthat can be used in various methods to prepare semiconductor materials.For processes involving inks of polymeric precursors, the controlleddeposition of such inks can provide composition gradients by using twoor more inks The polymeric precursor compounds and compositions of thisdisclosure can provide enhanced processability for solar cellproduction.

Certain polymeric precursor compounds and compositions of thisdisclosure provide the ability to be processed at relatively lowtemperatures, as well as the ability to use a variety of substratesincluding flexible polymers in solar cells.

Embodiments of Polymeric Precursors for CIS and CIGS Photovoltaics

Embodiments of this invention include:

A compound comprising repeating units {M^(A)(ER)(ER)} and{M^(B)(ER)(ER)}, wherein each M^(A) is Cu, each M^(B) is In or Ga, eachE is S, Se, or Te, and each R is independently selected, for eachoccurrence, from alkyl, aryl, heteroaryl, alkenyl, amido, silyl, andinorganic and organic ligands. Each E may be sulfur or selenium. Thecompound may be a CIGS, CIS or CGS precursor compound.

A compound comprising two or more repeating units {M^(A)(ER)(ER)} andtwo or more repeating units {M^(B)(ER)(ER)}, wherein each M^(A) is Cu,each M^(B) is In or Ga, each E is S, Se, or Te, and each R isindependently selected, for each occurrence, from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands.

A compound comprising repeating units {M^(A)(ER)(ER)} or{M^(B)(ER)(ER)}, wherein each M^(A) is Cu, each M^(B) is In or Ga, eachE is S, Se, or Te, and each R is independently selected, for eachoccurrence, from alkyl, aryl, heteroaryl, alkenyl, amido, silyl, andinorganic and organic ligands.

A polymeric compound comprising repeating units {M^(A)(ER)(ER)} and{M^(B)(ER)(ER)}, wherein each M^(A) is Cu, each M^(B) is In or Ga, eachE is S, Se, or Te, and each R is independently selected, for eachoccurrence, from alkyl, aryl, heteroaryl, alkenyl, amido, silyl, andinorganic and organic ligands.

The compound above wherein the compound has the empirical formulaCu_(x)(In_(1-y)Ga_(y))_(v)((S_(1-z)Se_(z))R)_(w), wherein x is from 0.5to 1.5, y is from 0 to 1, z is from 0 to 1, v is from 0.5 to 1.5, w isfrom 2 to 6, and R represents R groups, of which there are w in number,which are independently selected from alkyl, aryl, heteroaryl, alkenyl,amido, silyl, and inorganic and organic ligands.

The compound above wherein x is from 0.7 to 1.2, y is from 0 to 0.5, zis from 0.5 to 1, v is from 0.9 to 1.1, and w is from 2 to 6. Thecompound above wherein x is from 0.7 to 1.2, y is from 0 to 0.3, z isfrom 0.7 to 1, v is 1, and w is from 3 to 5. The compound above whereinx is from 0.7 to 1.2, y is from 0 to 0.2, z is from 0.8 to 1, v is 1,and w is from 3.5 to 4.5. The compound above wherein the compound isdeficient in Cu or enriched in Cu. The compound above wherein thecompound is an inorganic polymer or coordination polymer. The compoundabove wherein the compound is linear, branched, cyclic, or a mixture ofany of the foregoing. The compound above wherein each R is independentlyselected, for each occurrence, from (C1-8)alkyl, (C1-6)alkyl,(C1-4)alkyl, (C1-3)alkyl, or (C1-2)alkyl. The compound above wherein thecompound is an oil at a temperature below about 100° C. The compoundabove comprising three or more repeating units {M^(B)(ER)(ER)}. Thecompound above comprising three or more repeating units {M^(A)(ER)(ER)}.The compound above wherein the compound is an alternating copolymer, ablock copolymer, or a random copolymer.

The compound above further comprising the formula (AB)_(n), wherein A isthe repeat unit {M^(A)(ER)(ER)}, B is the repeat unit {M^(B)(ER)(ER)}, nis two or more, or n is three or more, and R is independently selected,for each occurrence, from alkyl, aryl, heteroaryl, alkenyl, amido,silyl, and inorganic and organic ligands. The compound above wherein thecompound has any one of the formulas: (RE)₂-BB(AB)_(n)(RE)₂-B(AB)_(n)B,(RE)₂-B(AB)_(n)B(AB)_(m), (RE)₂-(BA)_(n)BB, (RE)₂-B(BA)_(n)B,(RE)₂-(BA)_(n)B(BA)_(m)B, ^(cyclic)(AB)_(n), ^(cyclic)(BA)_(n),(RE)₂-(BB)(AABB)_(n), (RE)₂-(BB)(AABB)_(n)(AB)_(m),(RE)₂-(B)(AABB)_(n)(B)(AB)_(m), (RE)₂-[B(AB)_(n)]⁻, (RE)₂-[(BA)_(n)B]⁻,

(RE)₂-BB(AB¹)_(n)(AB²)_(m), (RE)₂-BB(AB¹)(AB²)_(m)(AB¹)_(p), and amixture thereof, wherein A is the repeat unit {M^(A)(ER)(ER)}, B is therepeat unit {M^(B)(ER)(ER)}, n is one or more, or n is two or more, or nis three or more, m is one or more, and p is one or more.

The compound above wherein the compound has any one of the repeat unitformulas: {Cu(S^(t)Bu)(S^(i)Pr)In(S^(i)Pr)₂};{Cu(S^(t)Bu)₂In(S^(t)Bu)₂}; {Cu(S^(t)Bu)(S^(n)Bu)In(S^(n)Bu)₂};{Cu(Se^(t)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)Ga(S^(t)Bu)₂}; {Cu(Se^(t)Bu)₂Ga(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂Ga(S^(t)Bu)₂}; {Cu(Se^(t)Bu)₂In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)In(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(s)Bu)In(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)Ga(Se^(i)PO₂};{Cu(S^(t)Bu)(S^(i)Pr)Ga(S^(i)Pr)₂},{Cu(Se^(t)Bu)(Se^(n)Bu)In(Se^(n)Bu)₂};{Cu(S^(t)Bu)(S^(i)Pr)In(S^(i)Pr)₂}; {Cu(S^(n)Bu)(S^(t)Bu)In(S^(t)Bu)₂};{Cu(Se^(n)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)Ga(S^(t)Bu)₂}; {Cu(S^(n)Bu)(S^(t)Bu)Ga(S^(t)Bu)₂};{Cu(Se^(s)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)In(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(s)Bu)In(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)Ga(Se^(i)Pr)₂};{Cu(S^(t)Bu)(S^(i)Pr)Ga(S^(i)Pr)₂},{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂};{Cu(S^(t)Bu)₂(In,Ga)(S^(t)Bu)₂}; {Cu(S^(t)Bu)(S^(n)Bu)(m,Ga)(S^(n)Bu)₂};{Cu(Se^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(n)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)₂(In,Ga)(Se^(t)Bu)₂}; {Cu(S^(t)Bu)₂(In,Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)₂(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(In,Ga)(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(In,Ga)(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(In,Ga)(Se^(i)Pr)₂};{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂},{Cu(Se^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(n)Bu)₂};{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂};{Cu(S^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(S^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(Se^(s)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(In,Ga)(Se^(i)Pr)₂};{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂}; {(1.2 Cu)(1.2Se^(t)Bu)(Se^(t)Bu)(0.7 In,0.3 Ga)(Se^(t)Bu)₂}; {(1.3 Cu)(1.3S^(t)Bu)(S^(t)Bu)(0.85 In,0.15 Ga)(S^(t)Bu)₂}; {(1.5 Cu)(1.5SeHexyl)(SeHexyl)(0.80 In,0.20 Ga)(SeHexyl)₂}; {(0.85 Cu)(0.85Se^(t)Bu)(Se^(t)Bu)(0.7 In,0.3 Ga)(Se^(n)Bu)₂}; {(0.9 Cu)(0.9S^(t)Bu)(S^(t)Bu)(0.85 In,0.15 Ga)(S^(t)Bu)₂}; {(0.75 Cu)(0.75S^(t)Bu)(S^(t)Bu)(0.80 In,0.20 Ga)(S^(t)Bu)₂}; {(0.8 Cu)(0.8Se^(t)Bu)(Se^(n)Bu)(0.75 In,0.25 Ga)(Se^(t)Bu)₂}; {(0.95 Cu)(0.95S^(t)Bu)(Se^(t)Bu)(0.70 In,0.30 Ga)(Se^(t)Bu)₂}; {(0.98 Cu)(0.98Se^(t)Bu)(S^(t)Bu)(0.600 In,0.400 Ga)(S^(t)Bu)₂}; {(0.835 Cu)(0.835Se^(t)Bu)₂(0.9 In,0.1 Ga)(Se^(t)Bu)₂}; {Cu(S^(t)Bu)₂(0.8 In,0.2Ga)(S^(t)Bu)₂}; {Cu(Se^(t)Bu)₂(0.75 In,0.25 Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(0.67 In,0.33 Ga)(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(0.875 In,0.125 Ga)(S^(S)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(0.99 In,0.01 Ga)(Se^(i)Pr)₂};{Cu(S^(t)Bu)(S^(i)Pr)(0.97 In,0.030 Ga)(S^(i)Pr)₂},{Cu(Se^(t)Bu)₂In(Se^(t)Bu)₂}; {Cu(Se^(s)Bu)₂Ga(Se^(s)Bu)₂};{Cu(S^(t)Bu)₂In(S^(t)Bu)₂}; {Cu(S^(t)Bu)₂In(S^(t)Bu)₂};{Cu(Se^(t)Bu)₂Ga(Se^(t)Bu)₂}; {Cu(Se^(t)Bu)₂Ga(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂In(S^(t)Bu)₂}; {Cu(Se^(t)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂Ga(S^(t)Bu)₂}; {Cu(Se^(n)Bu)(Se^(t)Bu)Ga(Se^(t)Bu)₂},{Cu(Se^(t)Bu)(Se^(n)Bu)(0.5 In,0.5 Ga)(Se^(n)Bu)₂};{Cu(Se^(t)Bu)(Se^(n)Bu)(0.75 In,0.25 Ga)(Se^(n)Bu)₂}; {Cu(S^(t)Bu)₂(0.75In,0.25 Ga)(S^(t)Bu)₂}; {Cu(S^(t)Bu)₂(0.9 In,0.1 Ga)(S^(t)Bu)₂},{Cu(Se(n-pentyl))(Se^(n)Bu)(0.5 In,0.5 Ga)(Se^(n)Bu)₂};{Cu(Se(n-hexyl))(S^(t)Bu)(0.75 In,0.25 Ga)(Se^(n)Bu)₂};{Cu(S(n-heptyl))(S^(t)Bu)(0.75 In,0.25 Ga)(S^(t)Bu)₂}; and{Cu(S(n-octyl))(S^(t)Bu)(0.9 In,0.1 Ga)(S^(t)Bu)₂}.

An ink comprising one or more compounds above and one or more carriers.The ink above wherein the ink is a solution of the compounds in anorganic carrier. The ink above wherein the ink is a slurry or suspensionof the compounds in an organic carrier. The ink above further comprisinga dopant or alkali dopant. The ink above further comprising adding anadditional indium-containing compound, an additional gallium-containingcompound, or a molybdenum-containing compound. The ink above furthercomprising one or more components selected from the group of asurfactant, a dispersant, an emulsifier, an anti-foaming agent, a dryer,a filler, a resin binder, a thickener, a viscosity modifier, ananti-oxidant, a flow agent, a plasticizer, a conductivity agent, acrystallization promoter, an extender, a film conditioner, an adhesionpromoter, and a dye. The ink above further comprising one or morecomponents selected from the group of a conducting polymer, coppermetal, indium metal, gallium metal, zinc metal, an alkali metal, analkali metal salt, an alkaline earth metal salt, a sodium chalcogenate,a calcium chalcogenate, cadmium sulfide, cadmium selenide, cadmiumtelluride, indium sulfide, indium selenide, indium telluride, galliumsulfide, gallium selenide, gallium telluride, zinc sulfide, zincselenide, zinc telluride, copper sulfide, copper selenide, coppertelluride, molybdenum sulfide, molybdenum selenide, molybdenumtelluride, and mixtures of any of the foregoing.

A method for making a precursor compound comprising:

a) providing monomer compounds M^(B1)(ER)₃, M^(B2)(ER)₃, and M^(A)(ER);and

b) contacting the monomer compounds;

wherein M^(B1) is In, M^(B2) is Ga, M^(A) is Cu, each E is S, Se, or Te,and R is independently selected, for each occurrence, from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands.The method above wherein M^(B1) and M^(B2) are both In or both Ga. Themethod above wherein the monomer compounds are contacted in a process ofdepositing, spraying, coating, or printing. The method above wherein themonomer compounds are contacted at a temperature of from about −60° C.to about 100° C., or from about 0° C. to about 200° C.

A compound made by a process comprising reacting monomers M^(B1)(ER)₃,M^(B2)(ER)₃, and M^(A)(ER), wherein M^(B1) is In, M^(B2) is Ga, M^(A) isCu, each E is S, Se, or Te, and R is independently selected, for eachoccurrence, from alkyl, aryl, heteroaryl, alkenyl, amido, silyl, andinorganic and organic ligands. The compound above wherein M^(B1) andM^(B2) are both In. The compound above wherein the compound has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)((S_(1-z)Se_(z))R)_(w),wherein x is from 0.5 to 1.5, y is from 0 to 1, z is from 0 to 1, v isfrom 0.5 to 1.5, w is from 2 to 6, and R represents R groups, of whichthere are w in number, which are independently selected from alkyl,aryl, heteroaryl, alkenyl, amido, silyl, and inorganic and organicligands. The compound of above wherein x is from 0.7 to 1.2, y is from 0to 0.5, z is from 0.5 to 1, v is from 0.9 to 1.1, and w is from 2 to 6.The compound above wherein x is from 0.7 to 1.2, y is from 0 to 0.3, zis from 0.7 to 1, v is 1, and w is from 3 to 5. The compound abovewherein x is from 0.7 to 1.2, y is from 0 to 0.2, z is from 0.8 to 1, vis 1, and w is from 3.5 to 4.5.

An article comprising one or more compounds or inks described abovedeposited onto a substrate. The article above wherein the depositing isdone by spraying, spray coating, spray deposition, spray pyrolysis,printing, screen printing, inkjet printing, aerosol jet printing, inkprinting, jet printing, stamp/pad printing, transfer printing, padprinting, flexographic printing, gravure printing, contact printing,reverse printing, thermal printing, lithography, electrophotographicprinting, electrodepositing, electroplating, electroless plating, bathdeposition, coating, wet coating, spin coating, knife coating, rollercoating, rod coating, slot die coating, meyerbar coating, lip directcoating, capillary coating, liquid deposition, solution deposition,layer-by-layer deposition, spin casting, solution casting, andcombinations of any of the forgoing. The article above wherein thesubstrate is selected from the group of a semiconductor, a dopedsemiconductor, silicon, gallium arsenide, insulators, glass, molybdenumglass, silicon dioxide, titanium dioxide, zinc oxide, silicon nitride, ametal, a metal foil, molybdenum, aluminum, beryllium, cadmium, cerium,chromium, cobalt, copper, gallium, gold, lead, manganese, molybdenum,nickel, palladium, platinum, rhenium, rhodium, silver, stainless steel,steel, iron, strontium, tin, titanium, tungsten, zinc, zirconium, ametal alloy, a metal silicide, a metal carbide, a polymer, a plastic, aconductive polymer, a copolymer, a polymer blend, a polyethyleneterephthalate, a polycarbonate, a polyester, a polyester film, a mylar,a polyvinyl fluoride, polyvinylidene fluoride, a polyethylene, apolyetherimide, a polyethersulfone, a polyetherketone, a polyimide, apolyvinylchloride, an acrylonitrile butadiene styrene polymer, asilicone, an epoxy, paper, coated paper, and combinations of any of theforgoing. The article above wherein the substrate is a shaped substrateincluding a tube, a cylinder, a roller, a rod, a pin, a shaft, a plane,a plate, a blade, a vane, a curved surface or a spheroid.

A method for making an article, the method comprising:

(a) providing one or more compounds or inks described above;

(b) providing a substrate; and

(c) depositing the compounds or inks onto the substrate.

The method above wherein step (c) is repeated. The method above furthercomprising heating the substrate at a temperature of from about 100° C.to about 400° C. to convert the compounds or inks to a material. Themethod above further comprising heating the substrate at a temperatureof from about 100° C. to about 400° C. to convert the compounds or inksto a material, followed by repeating step (c). The method above furthercomprising annealing the material by heating the substrate at atemperature of from about 300° C. to about 650° C. The method abovefurther comprising heating the substrate at a temperature of from about100° C. to about 400° C. to convert the compounds or inks to a material,and annealing the material by heating the substrate at a temperature offrom about 300° C. to about 650° C. The method above further comprisingheating the substrate at a temperature of from about 100° C. to about400° C. to convert the compounds or inks to a material, depositing thecompounds or inks onto the substrate, and annealing the material byheating the substrate at a temperature of from about 300° C. to about650° C.

The method above further comprising:

(d) heating the substrate at a temperature of from about 100° C. toabout 400° C. to convert the compounds or inks to a material;

(e) depositing the compounds or inks onto the substrate;

(f) repeating steps (d) and (e); and

(g) annealing the material by heating the substrate at a temperature offrom about 300° C. to about 650° C.

The method above further comprising:

(d) heating the substrate at a temperature of from about 100° C. toabout 400° C. to convert the compounds or inks to a material;

(e) annealing the material by heating the substrate at a temperature offrom about 300° C. to about 650° C.; and

(f) repeating steps (c), (d) and (e).

The method above further comprising an optional step of selenization orsulfurization, either before, during or after any step of heating orannealing. An article made by the method above. A photovoltaic devicemade by the method above.

A material having the empirical formulaCu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z)), wherein x is from 0.5 to 1.5,y is from 0 to 1, and z is from 0 to 1, v is from 0.5 to 1.5, and w isfrom 1.5 to 2.5. The material above wherein x is from 0.7 to 1.2, y isfrom 0 to 0.5, and z is from 0.5 to 1, v is from 0.9 to 1.1, and w isfrom 1.5 to 2.5. The material above wherein x is from 0.7 to 1.2, y isfrom 0 to 0.3, and z is from 0.7 to 1, v is 1, and w is from 1.5 to 2.5.The material above wherein x is from 0.7 to 1.2, y is from 0 to 0.2, andz is from 0.8 to 1, v is 1, and w is from 2.0 to 2.4. The material abovewherein the material is a semiconductor. The material above wherein thematerial is in the form of a thin film. An optoelectronic devicecomprising the material above.

A method for making a material comprising,

(a) providing one or more compounds or inks above;

(b) providing a substrate;

(c) depositing the compounds or inks onto the substrate; and

(d) heating the substrate at a temperature of from about 20° C. to about650° C. in an inert atmosphere, thereby producing a material having athickness of from 0.001 to 100 micrometers.

A thin film material made by a process comprising,

(a) providing one or more compounds or inks above;

(b) providing a substrate;

(c) depositing the compounds or inks onto the substrate; and

(d) heating the substrate at a temperature of from about 20° C. to about650° C. in an inert atmosphere, thereby producing a thin film materialhaving a thickness of from 0.001 to 100 micrometers. The thin filmmaterial above wherein the substrate is heating at a temperature of fromabout 100° C. to about 550° C., or from about 200° C. to about 400° C.

A photovoltaic absorber having the empirical formulaCu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), wherein x is from 0.5 to1.5, y is from 0 to 1, and z is from 0 to 1, v is from 0.5 to 1.5, and wis from 1.5 to 2.5. The photovoltaic absorber above wherein x is from0.7 to 1.2, y is from 0 to 0.5, and z is from 0.5 to 1, v is from 0.9 to1.1, and w is from 1.5 to 2.5. The photovoltaic absorber above wherein xis from 0.7 to 1.2, y is from 0 to 0.3, and z is from 0.7 to 1, v is 1,and w is from 1.5 to 2.5. The photovoltaic absorber above wherein x isfrom 0.7 to 1.2, y is from 0 to 0.2, and z is from 0.8 to 1,v is 1, andw is from 2.0 to 2.4. A photovoltaic device comprising a photovoltaicabsorber above. A system for providing electrical power comprising aphotovoltaic device above. A method for providing electrical powercomprising using a photovoltaic system above to convert light intoelectrical energy.

A method for making a photovoltaic absorber layer on a substratecomprising,

(a) providing one or more compounds or inks above;

(b) providing a substrate;

(c) depositing the compounds or inks onto the substrate; and

(d) heating the substrate at a temperature of from about 100° C. toabout 650° C. in an inert atmosphere, thereby producing a photovoltaicabsorber layer having a thickness of from 0.001 to 100 micrometers.

Empirical Formulas of Precursor Compounds

This disclosure provides a range of polymeric precursor compounds havingtwo or more different metal atoms and chalcogen atoms.

In certain aspects, a polymeric precursor compound contains metal atoms,and atoms of Group 13, as well as combinations thereof. Any of theseatoms may be bonded to one or more atoms selected from atoms of Group15, S, Se, and Te, as well as one or more ligands.

A polymeric precursor compound may be a neutral compound, or an ionicform, or have a charged complex or counterion. In some embodiments, anionic form of a polymeric precursor compound may contain a divalentmetal atom, or a divalent metal atom as a counterion.

A polymeric precursor compound may contain atoms selected from thetransition metals of Group 3 through Group 12, B, Al, Ga, In, Tl, Si,Ge, Sn, Pb, As, Sb, and Bi. Any of these atoms may be bonded to one ormore atoms selected from atoms of Group 15, S, Se, and Te, as well asone or more ligands.

A polymeric precursor compound may contain atoms selected from Ni, Pd,Pt, Cu, Ag, Au, Zn, Cd, Hg, B, Al, Ga, In, Tl, Si, Ge, Sn, Pb, and Bi.Any of these atoms may be bonded to one or more atoms selected fromatoms of Group 15, S, Se, and Te, as well as one or more ligands.

In some embodiments, a polymeric precursor compound may contain atomsselected from Cu, Zn, Ga, In, Tl, Si, Ge, Sn, and Pb. Any of these atomsmay be bonded to one or more atoms selected from atoms of Group 15, S,Se, and Te, as well as one or more ligands.

In some embodiments, a polymeric precursor compound may contain atomsselected from Cu, Zn, Ga, In, Tl, Si, Ge, Sn, and Pb. Any of these atomsmay be bonded to one or more chalcogen atoms, as well as one or moreligands.

In some variations, a polymeric precursor compound may contain atomsselected from Cu, Ga, and In. Any of these atoms may be bonded to one ormore atoms selected from S, Se, and Te, as well as one or more ligands.

Polymeric Precursor Structure and Properties (MPP)

A polymeric precursor compound of this disclosure is stable at ambienttemperatures. Polymeric precursors can be used for making layeredmaterials, optoelectronic materials, and devices. Using polymericprecursors advantageously allows control of the stoichiometry,structure, and ratios of various atoms in a material, layer, orsemiconductor.

Polymeric precursor compounds of this invention may be solids, solidswith low melting temperatures, semisolids, flowable solids, gums, orrubber-like solids, oily substances, or liquids at ambient temperatures,or temperatures moderately elevated from ambient. Embodiments of thisdisclosure that are fluids at temperatures moderately elevated fromambient can provide superior processability for production of solarcells and other products, as well as the enhanced ability to beprocessed on a variety of substrates including flexible substrates.

In general, a polymeric precursor compound can be processed through theapplication of heat, light, kinetic, mechanical or other energy to beconverted to a material, including a semiconductor material. In theseprocesses, a polymeric precursor compound undergoes a transition tobecome a material. The conversion of a polymeric precursor compound to amaterial can be done in processes known in the art, as well as the novelprocesses of this disclosure.

Embodiments of this invention may further provide processes for makingoptoelectronic materials. Following the synthesis of a polymericprecursor compound, the compound can be deposited, sprayed, or printedonto a substrate by various means. Conversion of the polymeric precursorcompound to a material can be done during or after the process ofdepositing, spraying, or printing the compound onto the substrate.

A polymeric precursor compound of this disclosure may have a transitiontemperature below about 400° C., or below about 300° C., or below about280° C., or below about 260° C., or below about 240° C., or below about220° C., or below about 200° C.

In some aspects, polymeric precursors of this disclosure includemolecules that are melt processable at temperatures below about 100° C.In certain aspects, a polymeric precursor can be fluid, flowable,flowable melt, or semisolid at relatively low temperatures and can beprocessed as a neat solid, semisolid, neat flowable melt, flowablesolid, gum, rubber-like solid, oily substance, or liquid. In certainembodiments, a polymeric precursor is melt processable as a flowablemelt at a temperature below about 200° C., or below about 180° C., orbelow about 160° C., or below about 140° C., or below about 120° C., orbelow about 100° C., or below about 80° C., or below about 60° C., orbelow about 40° C.

In some variations of this invention, a uniform thin film of a polymericprecursor compound may provide a self-healing film which is thermallyprocessable to a material or semiconductor layer.

A polymeric precursor compound of this invention can be crystalline oramorphous, and can be soluble in various non-aqueous solvents.

A polymeric precursor compound may contain ligands, or ligand fragments,or portions of ligands that can be removed under mild conditions, atrelatively low temperatures, and therefore provide a facile route toconvert the polymeric precursor to a material or semiconductor. Theligands, or some atoms of the ligands, may be removable in variousprocesses, including certain methods for depositing, spraying, andprinting, as well as by application of energy.

These advantageous features allow enhanced control over the structure ofa semiconductor material made with the polymeric precursor compounds ofthis invention.

Polymeric Precursors for Semiconductors and Optoelectronics (MPP)

This invention provides a range of polymeric precursor structures,compositions, and molecules having two or more different metal atoms.

In some embodiments, a polymeric precursor compound contains atoms M^(B)of Group 13 selected from Ga and In.

These polymeric precursor compounds further contain monovalent metalatoms M^(A) which may be Cu.

The polymeric precursors of this disclosure can be considered inorganicpolymers or coordination polymers.

The polymeric precursors of this disclosure may be represented indifferent ways, using different formulas to describe the same structure.

Embodiments of this invention further provide polymeric precursors thatcan be described as AB alternating addition copolymers.

The AB alternating addition copolymer is in general composed of repeatunits A and B. The repeat units A and B are each derived from a monomer.The repeat units A and B may also be referred to as being monomers,although the empirical formula of monomer A is different from theempirical formula of repeat unit A.

The monomer for M^(A) can be M^(A)(ER), where M^(A) is Cu.

The monomer for M^(B) can be M^(B)(ER)₃, where M^(B) is Ga or In.

In a polymeric precursor, monomers of A link to monomers of B to providea polymer chain, whether linear, cyclic, or branched, or of any othershape, that has repeat units A, each having the formula {M^(A)(ER)₂},and repeat units B, each having the formula {M^(B)(ER)₂}. The repeatunits A and B may appear in alternating order in the chain, for example,•••ABABABABAB•••.

In some embodiments, a polymeric precursor may have different atomsM^(B) selected from Ga and In, where the different atoms appear inrandom order in the structure.

The polymeric precursor compounds of this invention may be made with anydesired stoichiometry with respect to the number of different Group 13elements and their respective ratios. The stoichiometry of a polymericprecursor compound may be controlled through the concentrations ofmonomers, or repeating units in the polymer chains of the precursors. Apolymeric precursor compound may be made with any desired stoichiometrywith respect to the number of different Group 13 elements and theirrespective ratios.

In some aspects, this disclosure provides polymeric precursors which areinorganic AB alternating addition copolymers having one of the followingFormulas 1 through 13:

(RE)₂-[B(AB)_(n)]⁻  Formula 1:

(RE)₂-[(BA)_(n)B]⁻  Formula 2:

(RE)₂-BB(AB)_(n)  Formula 3:

(RE)₂-B(AB)B  Formula 4:

(RE)₂-B(AB)_(n)B(AB)_(m)  Formula 5:

(RE)₂-(BA)BB  Formula 6:

(RE)₂-B(BA)_(n)B  Formula 7:

(RE)₂-(BA)_(n)B(BA)_(m)B  Formula 8:

^(cyclic)(AB)_(n)  Formula 9:

^(cyclic)(BA)_(n)  Formula 10:

(RE)₂-(BB)(AABB)_(n)  Formula 11:

(RE)₂-(BB)(AABB)_(n)(AB)_(m)  Formula 12:

(RE)₂-(B)(AABB)_(n)(B)(AB)_(m)  Formula 13:

where A and B are as defined above, E is S, Se, or Te, and R is definedbelow.

Formulas 1 and 2 describe ionic forms that have a counterion orcounterions not shown.

The formulas RE-B(AB)_(n) and RE-(BA)_(n)B may describe stable moleculesunder certain conditions.

For example, an embodiment of a polymeric precursor compound of Formula4 is shown in FIG. 1. As shown in FIG. 1, the structure of the compoundcan be represented by the formula (RE)₂BABABB, wherein A is the repeatunit {M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is a chalcogen,and R is a functional group defined below.

In another example, an embodiment of a polymeric precursor compound ofFormula 5 is shown in FIG. 2. As shown in FIG. 2, the structure of thecompound can be represented by the formula (RE)₂BABABBABAB, wherein A isthe repeat unit {M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is achalcogen, and R is a functional group defined below.

In a further example, an embodiment of a polymeric precursor compound ofFormula 6 is shown in FIG. 3. As shown in FIG. 3, the structure of thecompound can be represented by the formula (RE)₂BA(BA)BB, wherein A isthe repeat unit {M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is achalcogen, and R is a functional group defined below.

In another example, an embodiment of a polymeric precursor compound ofFormula 8 is shown in FIG. 4. As shown in FIG. 4, the structure of thecompound can be represented by the formula (RE)₂BA(BA)B(BA)_(m)B,wherein A is the repeat unit {M^(A)(ER)₂}, B is the repeat unit{M^(B)(ER)₂}, E is a chalcogen, and R is a functional group definedbelow.

In a further example, an embodiment of a polymeric precursor compound ofFormula 10 is shown in FIG. 5. As shown in FIG. 5, the structure of thecompound can be represented by the formula ^(cyclic)(BA)₄, wherein A isthe repeat unit {M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is achalcogen, and R is a functional group defined below.

A polymeric precursor having one of Formulas 1-8 and 11-13 may be of anylength or molecular size. The values of n and m can be one (1) or more.In certain embodiments, the values of n and m are 2 or more, or 3 ormore, or 4 or more, or 5 or more, or 6 or more, or 7 or more, or 8 ormore, or 9 or more, or 10 or more. In some embodiments, n and m areindependently from 2 to about one million, or from 2 to about 100,000,or from 2 to about 10,000, or from 2 to about 5000, or from 2 to about1000, or from 2 to about 500, or from 2 to about 100, or from 2 to about50.

A cyclic polymeric precursor having one of Formulas 9 or 10 may be ofany molecular size. The value of n may be two (2) or more. In certainvariations, the values of n and m are 2 or more, or 3 or more, or 4 ormore, or 5 or more, or 6 or more, or 7 or more, or 8 or more, or 9 ormore, or 10 or more. In some embodiments, for cyclic Formulas 9 and 10,n is from 2 to about 50, or from 2 to about 20, or from 2 to about 16,or from 2 to about 14, or from 2 to about 12, or from 2 to about 10, orfrom 2 to about 8.

In another aspect, the repeat units {M^(B)(ER)₂} and {M^(A)(ER)₂} may beconsidered “handed” because the metal atom M^(A) and the Group 13 atomM^(B) appear on the left, while the chalcogen atom E appears to theright side. Thus, a linear terminated chain will in general require anadditional chalcogen group or groups on the left terminus, as inFormulas 1-8 and 11-13, to complete the structure. A cyclic chain, asdescribed by Formulas 9 and 10, does not require an additional chalcogengroup or groups for termination.

In certain aspects, structures of Formulas 1-8 and 11-13, where n and mare one (1), may be described as adducts. For example, adducts include(RE)₂-BBAB, (RE)₂-BABB, and (RE)₂-BABBAB.

In some embodiments, a polymeric precursor may include a structure thatis an AABB alternating block copolymer. For example, a polymericprecursor or portions of a precursor structure may contain one or moreconsecutive repeat units {AABB}. A polymeric precursor having an AABBalternating block copolymer may be represented by any one of Formulas 11to 13 above.

In some aspects, this disclosure provides polymeric precursors which areinorganic AB alternating addition copolymers having the repeat units ofFormula 14

where atoms M^(B) are atoms of Group 13 selected from Ga and In, and Eis S, Se, or Te.

In certain aspects, this invention provides polymeric precursors havinga number n of the repeat units of Formula 14, where n may be 1 or more,or 2 or more, or 3 or more, or 4 or more, or 5 or more, or 6 or more, or7 or more, or 8 or more, or 9 or more, or 10 or more, or 11 or more, or12 or more.

The AB copolymer of Formula 14 may also be represented as (AB) or (BA),which represents a polymer of any chain length. Another way to representcertain AB copolymers is the formula •••ABAB•••.

In further variations, this invention provides polymeric precursors thatmay be represented by Formula 15

where atoms M^(B1) and M^(B2) are the same or different atoms of Group13 selected from Ga and In, E is S, Se, or Te, and p is one (1) or more.

In further aspects, this invention provides polymeric precursors whichmay be represented by Formula 16

where atoms M^(B1) and M^(B2) are the same or different atoms of Group13 selected from Ga and In, atoms M^(A1) and M^(A2) are Cu, E is S, Se,or Te, and p is one (1) or more.

In another aspect, this disclosure provides inorganic AB alternatingcopolymers which may be represented by Formula 17

••••••AB¹AB²AB³••••••  Formula 17

where B¹, B², and B³ are repeat units containing atoms M^(B1), M^(B2),and M^(B3), respectively, which are atoms of Ga or In.

Certain empirical formulas for monomers and polymeric precursors of thisinvention are summarized in Table 1.

TABLE 1 Empirical formulas for monomers, repeat units and polymericprecursors Formula Representative Constitutional Chain Unit DescriptionA {M^(A)(ER)₂} From monomer M^(A)(ER), where M^(A) is Cu B {M^(B)(ER)₂}From monomer M^(B)(ER)₃, where M^(B) is Ga or In AB{M^(A)(ER)₂M^(B)(ER)₂} Polymer chain repeat unit ABA{M^(A)(ER)₂M^(B)(ER)₂M^(A)(ER)₂} An adduct trimer, or oligomer B¹AB²{M^(B1)(ER)₂M^(A)(ER)₂M^(B2)(ER)₂} Polymer chain repeat unit, M^(B1) andM^(B2) may be the same or different, a trimer or oligomer AB¹AB²{M^(A)(ER)₂M^(B1)(ER)₂M^(A)(ER)₂M^(B2)(ER)₂} Alternating copolymer(AB)_(n), a tetramer or oligomer A^(B1)A^(B2)A^(B1){M^(A)(ER)₂M^(B1)(ER)₂M^(A)(ER)₂M^(B2)(ER)₂M^(A)(ER)₂M^(B1)(ER)₂}Polymer, or an AB trimer, or an oligomer (AB)_(n) or (BA)_(n)

Polymer of any chain length •••AABB•••

Polymer of any length, whether linear, branched, or cyclic {AABB}

AABB alternating block copolymer ^(cyclic)(AB)₄ or ^(cyclic)(BA)₄

Cyclic polymer chain, oligomer or octamer

In Table 1, the “representative constitutional chain unit” refers to therepeating unit of the polymer chain. In general, the number andappearance of electrons, ligands, or R groups in a representativeconstitutional chain repeating unit does not necessarily reflect theoxidation state of the metal atom. For example, the chain repeating unitA, which is {M^(A)(ER)₂}, arises from the monomer M^(A)(ER), where M^(A)is a metal atom of monovalent oxidation state 1 (I or one) such as Cu.It is to be understood that the repeating unit exists in the polymerchain bonded to two other repeating units, or to a repeating unit and achain terminating unit. Likewise, the chain repeating unit B, which is{M^(B)(ER)₂}, arises from the monomer M^(B)(ER)₃, where M^(B) is a Group13 atom of trivalent oxidation state 3 (III or three) selected from Gaand In. In one aspect, monomer M^(A)(ER), and monomer M^(B)(ER)₃,combine to form an AB repeating unit, which is {M^(A)(ER)₂M^(B)(ER)₂}.

In some aspects, this disclosure provides AB alternating copolymerswhich may also be alternating with respect to M^(A) or M^(B). Apolymeric precursor that is alternating with respect to M^(A) maycontain chain regions having alternating atoms M^(A1) and M^(A2). Apolymeric precursor that is alternating with respect to M^(B) maycontain chain regions having alternating atoms M^(B1) and M^(B2).

In further aspects, this disclosure provides AB alternating blockcopolymers which may contain one or more blocks of n repeat units,represented as (AB¹) or (B¹A)_(n), where the block of repeat unitscontains only one kind of atom M^(B1) selected from Group 13. A blockmay also be a repeat unit represented as (A¹B) or (BA¹)_(n), where theblock of repeat units contains only one kind of atom M^(A1). A polymericprecursor of this disclosure may contain one or more blocks of repeatunits having different Group 13 atoms in each block, or different atomsM^(A) in each block. For example, a polymeric precursor may have one ofthe following formulas:

(RE)₂-BB(AB¹)_(n)(AB²)_(m)  Formula 18:

(RE)₂-BB(AB¹)_(n)(AB²)_(m)(AB¹)_(p)  Formula 19:

where B¹ and B² represent repeat units {M^(B1)(ER)₂} and {M^(B2)(ER)₂},respectively, where M^(B1) and M^(B2) are Ga and In, respectively. InFormulas 18 through 19, the values of n, m, and p may be 2 or more, or 3or more, or 4 or more, or 5 or more, or 6 or more, or 7 or more, or 8 ormore, or 9 or more, or 10 or more, or 11 or more, or 12 or more.

In certain embodiments, an M^(B) monomer can contain a chelating group-ERE-, for example, having the formula M^(B)(ERE).

In some embodiments, a monomer may exist in a dimeric form under ambientconditions, or a trimeric or higher form, and can be used as a reagentin such forms. It is understood that the term monomer would refer to allsuch forms, whether found under ambient conditions, or found during theprocess for synthesizing a polymeric precursor from the monomer. Theformulas M^(A)(ER) and M^(B)(ER)₃, for example, should be taken toencompass the monomer in such naturally-occurring dimeric or higherforms, if any. A monomer in a dimeric or higher form, when used as areagent can provide the monomer form. For example, compounds of theempirical formula Cu(ER) may occur in aggregated forms that areinsoluble, and when used as a reagent can provide the monomer form forreaction with M^(B)(ER)₃.

The polymeric precursors of this invention obtained by reacting monomersM^(A)(ER) and M^(B)(ER)₃ can be advantageously highly soluble in organicsolvent, whereas one or more of the monomers may have been insoluble.

As used herein, the terms “polymer” and “polymeric” refer to apolymerized moiety, a polymerized monomer, a repeating chain made ofrepeating units, or a polymer chain or polymer molecule. A polymer orpolymer chain may be defined by recitation of its repeating unit orunits, and may have various shapes or connectivities such as linear,branched, cyclic, and dendrimeric. Unless otherwise specified, the termspolymer and polymeric include homopolymers, copolymers, blockcopolymers, alternating polymers, terpolymers, polymers containing anynumber of different monomers, oligomers, networks, two-dimensionalnetworks, three-dimensional networks, crosslinked polymers, short andlong chains, high and low molecular weight polymer chains,macromolecules, and other forms of repeating structures such asdendrimers. Polymers include those having linear, branched and cyclicpolymer chains, and polymers having long or short branches.

As used herein, the term “polymeric component” refers to a component ofa composition, where the component is a polymer, or may form a polymerby polymerization. The term polymeric component includes a polymerizablemonomer or polymerizable molecule. A polymeric component may have anycombination of the monomers or polymers which make up any of the examplepolymers described herein, or may be a blend of polymers.

Embodiments of this invention may further provide polymeric precursorshaving polymer chain structures with repeating units. The stoichiometryof these polymeric precursors may be precisely controlled to provideaccurate levels of any desired arbitrary ratio of particular atoms.Precursor compounds having controlled stoichiometry can be used to makebulk materials, layers, and semiconductor materials having controlledstoichiometry. In some aspects, precisely controlling the stoichiometryof a polymeric precursor may be achieved by controlling thestoichiometry of the reagents, reactants, monomers or compounds used toprepare the polymeric precursor.

For the polymeric precursors of this invention, the group R in theformulas above, or a portion thereof, may be a good leaving group inrelation to a transition of the polymeric precursor compound at elevatedtemperatures or upon application of energy.

The functional groups R in the formulas above and in Table 1 may each bethe same or different from the other and are groups attached through acarbon or non-carbon atom, including alkyl, aryl, heteroaryl, alkenyl,amido, silyl, and inorganic and organic ligands. In some embodiments,the groups R are each the same or different from the other and are alkylgroups attached through a carbon atom.

In some aspects, the monomer for M^(B) can be represented asM^(B)(ER¹)₃, and the monomer for M^(A) can be represented as M^(A)(ER²),where R¹ and R² are the same or different and are groups attachedthrough a carbon or non-carbon atom, including alkyl, aryl, heteroaryl,alkenyl, amido, silyl, and inorganic and organic ligands. In someembodiments, the groups R¹ and R² are each the same or different fromthe other and are alkyl groups attached through a carbon atom.

In certain variations, the monomer for M^(B) may be M^(B)(ER¹)(ER³)₂,where R¹ and R³ are different and are groups attached through a carbonor non-carbon atom, including alkyl, aryl, heteroaryl, alkenyl, amido,silyl, and inorganic and organic ligands. In some embodiments, thegroups R¹ and R³, of M^(B)(ER¹)(ER³)₂, are different and are alkylgroups attached through a carbon atom.

In further embodiments, the groups R may independently be (C1-22)alkylgroups. In these embodiments, the alkyl group may be a (C1)alkyl(methyl), or a (C2)alkyl (ethyl), or a (C3)alkyl, or a (C4)alkyl, or a(C5)alkyl, or a (C6)alkyl, or a (C7)alkyl, or a (C8)alkyl, or a(C9)alkyl, or a (C10)alkyl, or a (C11)alkyl, or a (C12)alkyl, or a(C13)alkyl, or a (C14)alkyl, or a (C15)alkyl, or a (C16)alkyl, or a(C17)alkyl, or a (C18)alkyl, or a (C19)alkyl, or a (C20)alkyl, or a(C21)alkyl, or a (C22)alkyl.

In certain embodiments, the groups R may independently be (C1-12)alkylgroups. In these embodiments, the alkyl group may be a (C1)alkyl(methyl), or a (C2)alkyl (ethyl), or a (C3)alkyl, or a (C4)alkyl, or a(C5)alkyl, or a (C6)alkyl, or a (C7)alkyl, or a (C8)alkyl, or a(C9)alkyl, or a (C10)alkyl, or a (C11)alkyl, or a (C12)alkyl.

In certain embodiments, the groups R may independently be (C1-6)alkylgroups. In these embodiments, the alkyl group may be a (C1)alkyl(methyl), or a (C2)alkyl (ethyl), or a (C3)alkyl, or a (C4)alkyl, or a(C5)alkyl, or a (C6)alkyl.

A polymeric precursor compound may be crystalline, or non-crystalline.

In some embodiments, a polymeric precursor may be a compound comprisingrepeating units {M^(B)(ER)(ER)} and {M^(A)(ER)(ER)}, wherein M^(A) is amonovalent metal atom of Cu, M^(B) is an atom of Group 13, E is S, Se,or Te, and R is independently selected, for each occurrence, from alkyl,aryl, heteroaryl, alkenyl, amido, silyl, and inorganic and organicligands. In certain embodiments, the atoms M^(B) in the repeating units{M^(B)(ER)(ER)} are randomly selected from atoms of Group 13. In certainvariations, M^(A) is Cu and the atoms M^(B) are selected from indium andgallium. E may be only selenium in a polymeric precursor, and the groupsR may be independently selected, for each occurrence, from (C1-6)alkyl.

Embodiments of this invention may further provide polymeric precursorsthat are linear, branched, cyclic, or a mixture of any of the foregoing.Some polymeric precursors may be a flowable melt at a temperature belowabout 100° C.

In some aspects, a polymeric precursor may contain n repeating units{M^(B)(ER)(ER)} and n repeating units {M^(A)(ER)(ER)}, wherein n is oneor more, or n is two or more, or n is four or more, or n is eight ormore. The repeating units {M^(B)(ER)(ER)} and {M^(A)(ER)(ER)} may bealternating. A polymeric precursor may be described by the formula (AB),wherein A is the repeat unit {M^(B)(ER)(ER)}, B is the repeat unit{M^(B)(ER)(ER)}, n is one or more, or n is two or more, or n is three ormore, and R is independently selected, for each occurrence, from alkyl,aryl, heteroaryl, alkenyl, amido, silyl, and inorganic and organicligands. In some variations, a polymeric precursor may have any one ofthe formulas (RE)₂-BB(AB)_(n), (RE)₂-B(AB)_(n)B, (RE)₂-B(AB)B(AB)_(m),(RE)₂-(BA)_(n)BB, (RE)₂-B(BA)_(n)B, (RE)₂-(BA)_(n)B(BA)_(m)B,^(cyclic)(AB)_(n), ^(cyclic)(BA)_(n), (RE)₂-(BB)(AABB)_(n),(RE)₂-(BB)(AABB)_(n)(AB)_(m), (RE)₂-(B)(AABB)_(n)(B)(AB)_(m),(RE)₂-[B(AB)_(n)]⁻, and (RE)₂-[(BA)_(n)B]⁻, wherein A is the repeat unit{M^(A)(ER)(ER)}, B is the repeat unit {M^(B)(ER)(ER)}, n is one or more,or n is two or more, or n is three or more, and m is one or more. Infurther aspects, a polymeric precursor may be a block copolymercontaining one or more blocks of repeat units, wherein each blockcontains only one kind of atom M^(B).

A precursor compound of this disclosure may be a combination of xequivalents of M^(A1)(ER), v*(1-y) equivalents of M^(B1)(ER)₃, v*yequivalents of M^(B2)(ER)₃, wherein M^(A1) is Cu, M^(B1) and M^(B2) aredifferent atoms of Group 13, wherein the compound has the empiricalformula M^(A1) _(x)(M^(B1) _(1-y)M^(B2) _(y))_(v)((S_(1-z)Se_(z))R)_(w),wherein x is from 0.5 to 1.5, y is from 0 to 1, z is from 0 to 1, v isfrom 0.5 to 1.5, w is from 2 to 6, and R represents R groups, of whichthere are w in number, independently selected from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands. Inthese embodiments, a precursor compound can have the stoichiometryuseful to prepare CIGS materials, including materials deficient in thequantity of a Group 11 atom.

In further embodiments, a precursor compound can contain S, Se and Te.

In some embodiments, a precursor compound can be a combination of zequivalents of M^(A1)(ER¹), x equivalents of M^(B1)(ER²)₃, y equivalentsof M^(B2)(ER³)₃, wherein M^(A1) is Cu, M^(B1) and M^(B2) are differentatoms of Group 13, wherein the compound has the empirical formulaCu_(z)In_(x)Ga_(y)(ER¹)_(z)(ER²)_(3x)(ER³)_(3y), z is from 0.5 to 1.5, xis from 0 to 1, y is from 0 to 1, x plus y is one, and wherein R¹, R²,R³ are the same or each different, and are independently selected, foreach occurrence, from alkyl, aryl, heteroaryl, alkenyl, amido, silyl,and inorganic and organic ligands. In these embodiments, a precursorcompound can have the stoichiometry useful to prepare CIGS materials,including materials deficient in the quantity of a Group 11 atom.

This disclosure provides a range of polymeric precursor compounds madeby reacting a first monomer M^(B)(ER¹)₃ with a second monomerM^(A)(ER²), where M^(A) is a monovalent metal atom of Cu, M^(B) is anatom of Group 13, E is S, Se, or Te, and R¹ and R² are the same ordifferent and are independently selected from alkyl, aryl, heteroaryl,alkenyl, amido, silyl, and inorganic and organic ligands. The compoundsmay contain n repeating units {M^(B)(ER)(ER)} and n repeating units{M^(A)(ER)(ER)}, wherein n is one or more, or n is two or more, or n isthree or more, and R is defined, for each occurrence, the same as R¹ andR².

A polymeric precursor molecule can be represented by the formula{M^(A)(ER)(ER)M^(B)(ER)(ER)}, or {M^(A)(ER)₂M^(B)(ER)₂}, which are eachunderstood to represent an {AB} repeating unit of a polymeric precursor(AB). This shorthand representation is used in the following paragraphsto describe further examples of polymeric precursors. Further, when morethan one kind of atom M^(B) is present, the amount of each kind may bespecified in these examples by the notation (x M^(B1),y M^(B2)). Forexample, the polymeric compound {Cu(Se^(n)Bu)₂(0.75 In,0.25Ga)(Se^(n)Bu)₂} is composed of repeating units, where the repeatingunits appear in random order, and 75% of the repeating units contain anindium atom and 25% contain a gallium atom.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(S^(t)Bu)(S^(i)Pr)In(S^(i)Pr)₂}; {Cu(S^(t)Bu)₂In(S^(t)Bu)₂};{Cu(S^(t)Bu)(S^(t)Bu)In(S^(n)Bu)₂};{Cu(Se^(t)Bu)(Se^(t)Bu)In(Se^(n)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)Ga(S^(t)Bu)₂}; {Cu(Se^(t)Bu)₂Ga(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂Ga(S^(t)Bu)₂}; {Cu(Se^(t)Bu)₂In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)In(Se¹PO₂}; {Cu(Se^(t)Bu)(S^(s)Bu)In(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)Ga(Se^(i)Pr)₂}; and{Cu(S^(t)Bu)(S^(i)Pr)Ga(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(Se^(t)Bu)(Se^(n)Bu)In(Se^(n)Bu)₂};{Cu(S^(t)Bu)(S^(i)Pr)In(S^(i)Pr)₂}; {Cu(S^(n)Bu)(S^(t)Bu)In(S^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)Ga(S^(t)Bu)₂}; {Cu(S^(t)Bu)(S^(t)Bu)Ga(S^(t)Bu)₂};{Cu(Se^(s)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)In(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(t)Bu)In(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)Ga(Se^(i)Pr)₂}; and{Cu(S^(t)Bu)(S^(i)Pr)Ga(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂};{Cu(S^(t)Bu)₂(In,Ga)(S^(t)Bu)₂};{Cu(S^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(n)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)₂(In,Ga)(Se^(t)Bu)₂}; {Cu(S^(t)Bu)₂(In,Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)₂(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(In,Ga)(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(In,Ga)(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(In,Ga)(Se^(i)Pr)₂}; and{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(Se^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(n)Bu)₂};{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂};{Cu(S^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(S^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(Se^(s)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(In,Ga)(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(In,Tl)(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(Ga,Tl)(Se^(i)Pr)₂}; and{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas: {(1.2 Cu)(1.2Se^(t)Bu)(Se^(t)Bu)(0.7 In,0.3 Ga)(Se^(n)Bu)₂}; {(1.3 Cu)(1.3S^(t)Bu)(S^(t)Bu)(0.85 In,0.15 Ga)(S^(t)Bu)₂}; and {(1.5 Cu)(1.5SeHexyl)(SeHexyl)(0.80 In,0.20 Ga)(SeHexyl)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas: {(0.85 Cu)(0.85Se^(t)Bu)(Se^(t)Bu)(0.7 In,0.3 Ga)(Se^(n)Bu)₂}; {(0.9 Cu)(0.9S^(t)Bu)(S^(t)Bu)(0.85 In,0.15 Ga)(S^(t)Bu)₂}; {(0.75 Cu)(0.75S^(t)Bu)(S^(t)Bu)(0.80 In,0.20 Ga)(S^(t)Bu)₂}; {(0.8 Cu)(0.8Se^(t)Bu)(Se^(n)Bu)(0.75 In,0.25 Ga)(Se^(n)Bu)₂}; {(0.95 Cu)(0.95S^(t)Bu)(Se^(t)Bu)(0.70 In,0.30 Ga)(Se^(t)Bu)₂}; {(0.98 Cu)(0.98Se^(t)Bu)(S^(t)Bu)(0.600 In,0.400 Ga)(S^(t)Bu)₂}; {(0.835 Cu)(0.835Se^(t)Bu)₂(0.9 In,0.1 Ga)(Se^(t)Bu)₂}; {Cu(S^(t)Bu)₂(0.8 In,0.2Ga)(S^(t)Bu)₂}; {Cu(Se^(t)Bu)₂(0.75 In,0.25 Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(0.67 In,0.33 Ga)(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(0.875 In,0.125 Ga)(S^(S)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(0.99 In,0.01 Ga)(Se^(i)Pr)₂}; and{Cu(S^(t)Bu)(S^(i)Pr)(0.97 In,0.030 Ga)(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(Se^(t)Bu)₂In(Se^(t)Bu)₂}; {Cu(Se^(t)Bu)₂Ga(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂In(S^(t)Bu)₂}; {Cu(S^(t)Bu)₂In(S^(n)Bu)₂};{Cu(Se^(t)Bu)₂Ga(Se^(n)Bu)₂}; {Cu(Se^(t)Bu)₂Ga(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂In(S^(t)Bu)₂}; {Cu(Se^(t)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂Ga(S^(t)Bu)₂}; and {Cu(Se^(t)Bu)(Se^(t)Bu)Ga(Se^(t)Bu)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(Se^(t)Bu)(Se^(t)Bu)(0.5 In,0.5 Ga)(Se^(n)Bu)₂};{Cu(Se^(t)Bu)(Se^(t)Bu)(0.75 In,0.25 Ga)(Se^(n)Bu)₂}; {Cu(S^(t)Bu)₂(0.75In,0.25 Ga)(S^(t)Bu)₂}; and {Cu(S^(t)Bu)₂(0.9 In,0.1 Ga)(S^(t)Bu)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(Se(n-pentyl))(Se^(n)Bu)(0.5 In,0.5 Ga)(Se^(n)Bu)₂};{Cu(Se(n-hexyl))(Se^(n)Bu)(0.75 In,0.25 Ga)(Se^(n)Bu)₂};{Cu(S(n-heptyl))(S^(t)Bu)(0.75 In,0.25 Ga)(S^(t)Bu)₂}; and{Cu(S(n-octyl))(S^(t)Bu)(0.9 In,0.1 Ga)(S^(t)Bu)₂}.

Preparation of Polymeric Precursors (MPP)

Embodiments of this invention provide a family of polymeric precursormolecules and compositions which can be synthesized from a compoundcontaining an atom M^(B) of Group 13 selected from Ga and In, and acompound containing a monovalent atom M^(A) of Cu.

Advantageously facile routes for the synthesis and isolation ofpolymeric precursor compounds of this invention have been discovered, asdescribed below.

This disclosure provides a range of polymeric precursor compositionswhich can be transformed into semiconductor materials andsemiconductors. In some aspects, the polymeric precursor compositionsare precursors for the formation of semiconductor materials andsemiconductors.

In some embodiments, the polymeric precursor compositions are sources orprecursors for the formation of absorber layers for solar cells,including CIS, copper-indium-chalcogen, and CIGS,copper-indium-gallium-chalcogen, absorber layers.

A polymeric precursor compound may be made with any desiredstoichiometry with respect to the number of different Group 13 elementsand their respective ratios.

As discussed below, a polymeric precursor compound may be made byreacting monomers to produce a polymer chain. The polymeric precursorformation reactions can include initiation, propagation, andtermination.

Methods for making a polymeric precursor may include the step ofcontacting a compound M^(B)(ER)₃ with a compound M^(A)(ER), where M^(A),M^(B), E, and R are as defined above.

As shown in Reaction Scheme 1, a method for making a polymeric precursormay include the step of contacting a compound M^(B)(ER¹)₃ with acompound M^(A)(ER²), where M^(A), M^(B), and E are as defined above andthe groups R¹ and R² of the compounds may be the same or different andare as defined above.

In Reaction Scheme 1, M^(B)(ER¹)₃ and M^(A)(ER²) are monomers that formthe first adduct 1, M^(A)(ER)₂M^(B)(ER)₂. Reaction Scheme 1 representsthe initiation of a polymerization of monomers. In one aspect, ReactionScheme 1 represents the formation of the intermediate adduct AB. Ingeneral, among other steps, the polymerization reaction may form polymerchains by adding monomers to the first adduct 1, so that the firstadduct 1 may be a transient molecule that is not observed when a longerchain is ultimately produced. When additional monomers are bound toeither end of the first adduct 1, then the first adduct 1 becomes arepeating unit AB in the polymer chain.

In general, to prepare a polymeric precursor, the compounds M^(B)(ER)₃and M^(A)(ER) can be generated by various reactions.

For example, a compound M^(A)(ER) can be prepared by reacting M^(A)Xwith M⁺(ER). M⁺(ER) can be prepared by reacting E with LiR to provideLi(ER). Li(ER) can be acidified to provide HER, which can be reactedwith Na(OR) or K(OR) to provide Na(ER) and K(ER), respectively. In thesereactions, E, R and M^(A) are as defined above.

In another example, a compound M^(A)(ER) can be prepared by reactingM^(A)X with (RE)Si(CH₃)₃. The compound (RE)Si(CH₃)₃ can be made byreacting M⁺(ER) with XSi(CH₃)₃, where M⁺ is Na, Li, or K, and X ishalogen.

In another example, a compound M^(A)(ER) can be prepared by reactingM^(A) ₂O with HER. In particular, Cu(ER) can be prepared by reactingCu₂O with HER.

For example, a compound M^(B)(ER)₃ can be prepared by reacting M^(B)X₃with M⁺(ER). M⁺(ER) can be prepared as described above.

In another example, a compound M^(B)(ER)₃ can be prepared by reactingM^(B)X₃ with (RE)Si(CH₃)₃. The compound (RE)Si(CH₃)₃ can be made asdescribed above.

In another example, a compound M^(B)(ER)₃ can be prepared by reactingM^(B)R₃ with HER.

Moreover, in the preparation of a polymeric precursor, a compoundM⁺M^(B)(ER)₄ can optionally be used in place of a portion of thecompound M^(B)(ER)₃. For example, a compound M⁺M^(B)(ER)₄ can beprepared by reacting M^(B)X₃ with 4 equivalents of M⁺(ER), where M⁺ isNa, Li, or K, and X is halogen. The compound M⁺(ER) can be prepared asdescribed above.

The propagation of the polymeric precursor can be represented in part bythe formulas in Reaction Scheme 2. The formulas in Reaction Scheme 2represent only some of the reactions and additions which may occur inpropagation of the polymeric precursor.

In Reaction Scheme 2, the addition of a monomer M^(B)(ER¹)₃ orM^(A)(ER²) to the first adduct 1, may produce additional adducts 2 and3, respectively. In one aspect, Reaction Scheme 2 represents theformation of the adduct (RE)-BAB, as well as the adduct intermediateAB-M^(A)(ER). In general, the adducts 2 and 3 may be transient moietiesthat are not observed when a longer chain is ultimately produced.

The products of the initial propagation steps may continue to addmonomers in propagation. As shown in Reaction Scheme 3, adduct 2 may adda monomer M^(B)(ER¹)₃ or M^(A)(ER²).

In one aspect, Reaction Scheme 3 represents the formation of theintermediate adduct (RE)-BAB-M^(A)(ER)₄, as well as the adduct(RE)₂-BBAB 6. In general, the molecules 4, 5 and 6 may be transientmolecules that are not observed when a longer chain is ultimatelyproduced.

Other reactions and additions which may occur include the addition ofcertain propagating chains to certain other propagating chains. Forexample, as shown in Reaction Scheme 4, adduct 1 may add to adduct 2 toform a longer chain.

In one aspect, Reaction Scheme 4 represents the formation of the adduct(RE)-BABAB 7.

Any of the moieties 4, 5, 6, and 7 may be transient, and may not beobserved when a longer chain is ultimately produced.

In some variations, a propagation step may provide a stable molecule.For example, moiety 6 may be a stable molecule.

In general, AB alternating block copolymers as described in Formulas 18through 19 may be prepared by sequential addition of the correspondingmonomers M^(B1)(ER)₃, M^(B2)(ER)₃, and M^(A)(ER) during polymerizationor propagation.

Certain reactions or additions of the polymeric precursor propagationmay include the formation of chain branches. As shown in Reaction Scheme5, the addition of a monomer M^(A)(ER²) to the adduct molecule 2 mayproduce a branched chain 8.

The propagation of the polymeric precursor can be represented in part bythe formulas in Reaction Schemes 2, 3, 4 and 5. The formulas in ReactionSchemes 2, 3, 4 and 5 represent only some representative reactions andadditions which may occur in propagation of the polymeric precursor.

Termination of the propagating polymer chain may occur by severalmechanisms. In general, because of the valencies of the atoms M^(A) andM^(B), a completed polymer chain may terminate in a M^(B) unit, but notan M^(A) unit. In some aspects, a chain terminating unit is a •••B unit,or a (ER)₂B••• unit.

In some aspects, the propagation of the polymeric precursor chain mayterminate when either of the monomers M^(B)(ER)₃ or M^(A)(ER) becomesdepleted.

In certain aspects, as shown in Reaction Scheme 6, the propagation ofthe polymeric precursor chain may terminate when a growing chainrepresented by the formula (RE)-B••••••B reacts with another chainhaving the same terminal (RE)-B unit to form a chain having the formulaB••••••BB••••••B.

In Reaction Scheme 6, two chains have combined, where the propagation ofthe polymer chain is essentially terminated and the product chain(RE)₂B••••••BB••••••B has chain terminating units that are B units.

In further aspects, the propagation of the polymeric precursor chain mayterminate when the growing chain forms a ring. As shown in ReactionScheme 7, a propagating chain such as 5 may terminate by cyclization inwhich the polymer chain forms a ring.

A polymeric precursor compound may be a single chain, or a distributionof chains having different lengths, structures or shapes, such asbranched, networked, dendrimeric, and cyclic shapes, as well ascombinations of the forgoing. A polymeric precursor compound may be anycombination of the molecules, adducts and chains described above inReaction Schemes 1 through 7.

A polymeric precursor of this disclosure may be made by the process ofproviding a first monomer compound having the formula M^(B)(ER¹)₃,providing a second monomer compound having the formula M^(A)(ER²), andcontacting the first monomer compound with the second monomer compound.In some embodiments, the first monomer compound may be a combination ofcompounds having the formulas M^(B1)(ER¹)₃ and M^(B2)(ER³)₃, whereinM^(B1) and M^(B2) are different atoms of Group 13, and R¹, R² and R³ arethe same or different and are independently selected from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands. Incertain aspects, the second monomer compound may be a combination ofcompounds having the formulas M^(A1)(ER²) and M^(A2)(ER³), whereinM^(A1) and M^(A2) are Cu, and R³ is defined the same as R¹ and R².

In further aspects, a method for making a polymeric precursor mayinclude the synthesis of a compound containing two or more atoms ofM^(B) and contacting the compound with a compound M^(A)(ER), whereM^(A), M^(B), E and R are as defined above. For example,(ER)₂M^(B1)(ER)₂M^(B2)(ER)₂ can be reacted with M^(A)(ER²), where M^(B1)and M^(B2) are the same or different atoms of Group 13.

Methods for making a polymeric precursor include embodiments in whichthe first monomer compound and the second monomer compound may becontacted in a process of depositing, spraying, coating, or printing. Incertain embodiments, the first monomer compound and the second monomercompound may be contacted at a temperature of from about −60° C. toabout 100° C.

Controlled Stoichiometry of Polymeric Precursors (MPP)

A polymeric precursor compound may be made with any desiredstoichiometry with respect to the number of different Group 13 elementsand their respective ratios.

In some embodiments, the stoichiometry of a polymeric precursor compoundmay be controlled through the numbers of equivalents of the monomers inthe formation reactions.

In some aspects, the monomers M^(B1)(ER)₃ and M^(B2)(ER¹)₃ can be usedfor polymerization. Examples of these monomers are In(ER)₃, andGa(ER¹)₃, where the groups R, R¹ are the same or different and aregroups attached through a carbon or non-carbon atom, including alkyl,aryl, heteroaryl, alkenyl, amido, silyl, and inorganic and organicligands. In some embodiments, the groups R, R¹ are the same or differentand are alkyl groups attached through a carbon atom.

In further aspects, the monomers M^(B1)(ER)(ER¹)₂ and M^(B2)(ER²)(ER³)₂can be used for polymerization, where the groups R, R¹, R², R³ are eachthe same or different from the others and are groups attached through acarbon or non-carbon atom, including alkyl, aryl, heteroaryl, alkenyl,amido, silyl, and inorganic and organic ligands. In some embodiments,the groups R, R¹, R², R³ are each the same or different from the othersand are alkyl groups attached through a carbon atom.

Embodiments of this invention may further provide that the stoichiometryof a polymeric precursor compound may be controlled to any desired levelthrough the adjustment of the amounts of each of the monomers providedin the formation reactions.

As shown in Reaction Scheme 8, a polymerization to form a polymericprecursor may be initiated with a mixture of monomers M^(A)(ER³),M^(B1)(ER¹)₃) and M^(B2)(ER²)₃ having any arbitrary ratios ofstoichiometry.

In Reaction Scheme 8, a polymerization can be performed with a mixtureof monomers in any desired amounts. In certain variations, apolymerization to form a polymeric precursor may be initiated with amixture of any combination of the monomers described above, where thenumber of equivalents of each monomer is adjusted to any arbitrarylevel.

In some aspects, for alternating copolymers of monomers M^(A)(ER) andM^(B)(ER)₃, the ratio of M^(A) to M^(B) in the polymeric precursor canbe controlled from a ratio as low as 1:2 in the unit BAB, for example,to a ratio of 1:1 in an alternating (AB)_(n) polymeric precursor, to aratio of 1.5:1 or higher. The ratio of M^(A) to M^(B) in the polymericprecursor may be 0.5 to 1.5, or 0.5 to 1, or 1 to 1, or 1 to 0.5, or 1.5to 0.5. As discussed above, in further embodiments, a polymericprecursor compound may be made with any desired stoichiometry withrespect to the number of different Group 13 elements and theirrespective ratios.

In certain aspects, a polymerization to form a polymeric precursor canbe done to form a polymeric precursor having any ratio of M^(A) toM^(B). As shown in Reaction Scheme 9, a polymeric precursor having thecomposition {p M^(A)(ER)/m M^(B1)(ER)₃/n M^(B2)(ER)₃} may be formedusing the mixture of monomers m M^(B1)(ER)₃+n M^(B2)(ER)₃+p M^(A)(ER).

In certain variations, any number of monomers of M^(A)(ER) and anynumber of monomers of M^(B)(ER)₃ can be used in the formation reactions.For example, a polymeric precursor may be made with the monomersM^(A)(ER), M^(B1)(ER)₃, and M^(B2)(ER¹)₃, where the number ofequivalents of each monomer is an independent and arbitrary amount.

For example, the ratios of the atoms M^(A):M^(B) in a polymericprecursor may be about 0.5:1 or greater, or about 0.6:1 or greater, orabout 0.7:1 or greater, or about 0.8:1 or greater, or about 0.9:1 orgreater, or about 0.95:1 or greater. In certain variations, the ratiosof the atoms M^(A):M^(B) in a polymeric precursor may be about 1:1 orgreater, or about 1.1:1 or greater.

In further examples, the ratios of the atoms M^(A):M^(B) in a polymericprecursor may be from about 0.5 to about 1.2, or from about 0.6 to about1.2, or from about 0.7 to about 1.1, or from about 0.8 to about 1.1, orfrom about 0.8 to about 1, or from about 0.9 to about 1. In someexamples, the ratios of the atoms M^(A):M^(B) in a polymeric precursormay be about 0.80, or about 0.82, or about 0.84, or about 0.86, or about0.88, or about 0.90, or about 0.92, or about 0.94, or about 0.96, orabout 0.98, or about 1.00, or about 1.02, or about 1.1, or about 1.2, orabout 1.3, or about 1.5. In the foregoing ratios M^(A):M^(B), the ratiorefers to the sum of all atoms of M^(A) or M^(B), respectively, whenthere are more than one kind of M^(A) or M^(B), such as M^(B1) andM^(B2).

As shown in Reaction Scheme 10, a polymeric precursor compound havingthe repeating unit composition {M^(A)(ER)₂(m M^(B1),n M^(B2))(ER)₂} maybe formed using the mixture of monomers m M^(B1)(ER)₃+nM^(B2)(ER)₃+M^(A)(ER).

In Reaction Scheme 10, the sum of m and n is one.

Embodiments of this invention may further provide a polymeric precursormade from monomers of M^(A)(ER) and M^(B)(ER)₃, where the total numberof equivalents of monomers of M^(A)(ER) is less than the total number ofequivalents of monomers of M^(B)(ER)₃. In certain embodiments, apolymeric precursor may be made that is substoichiometric or deficientin atoms of M^(A) relative to atoms of M^(B).

As used herein, the expression M^(A) is deficient, or M^(A) is deficientto M^(B) refers to a composition or formula in which there are feweratoms of M^(A) than M^(B).

As used herein, the expression M^(A) is enriched, or M^(A) is enrichedrelative to M^(B) refers to a composition or formula in which there aremore atoms of M^(A) than M^(B).

As shown in Reaction Scheme 11, a polymeric precursor having theempirical formula M^(A1) _(x)(M^(B1) _(1-y)M^(B2)_(y))_(v)((S_(1-z)Se_(z))R)_(w) may be formed using the mixture ofmonomers M^(B1)(ER)₃, M^(B2)(ER)₃ and M^(A1)(ER).

where w can be (3v+x).

A precursor compound of this disclosure may have the empirical formulaM^(A1) _(x)(M^(B1) _(1-y)M^(B2) _(y))_(v)((S_(1-z)Se_(z))R)_(w), whereinx is from 0.5 to 1.5, y is from 0 to 1, z is from 0 to 1, v is from 0.5to 1.5, w is from 2 to 6, and R represents R groups, of which there arew in number, independently selected from alkyl, aryl, heteroaryl,alkenyl, amido, silyl, and inorganic and organic ligands. In theseembodiments, a precursor compound can have the stoichiometry useful toprepare CIGS materials, including materials deficient in the quantity ofa Group 11 atom.

In some embodiments, the empirical formula of a polymeric precursor canbe Cu_(x)In_(v)((S_(1-z)Se_(z))R)_(w), where R is as defined above, x isfrom 0.5 to 1.5, v is from 0.5 to 1.5, z is from 0 to 1, and w is from 2to 6.

In some embodiments, the empirical formula of a polymeric precursor canbe Cu_(x)In_(v)((S_(1-z)Se_(z))R)_(w), where R is as defined above, x isfrom 0.7 to 1.2, v is from 0.7 to 1.2, z is from 0 to 1, and w is from 2to 6.

In some embodiments, the empirical formula of a polymeric precursor canbe Cu_(x)In_(v)((S_(1-z)Se_(z))R)_(w), where R is as defined above, x isfrom 0.8 to 1, v is from 0.8 to 1.1, z is from 0 to 1, and w is from 2to 6.

In some embodiments, the empirical formula of a polymeric precursor canbe Cu_(x)In_(v)((S_(1-z)Se_(z))R)_(w), where R is as defined above, x isfrom 0.8 to 0.95, v is from 0.95 to 1.05, z is from 0 to 1, and w isfrom 3.6 to 4.4.

In some embodiments, the empirical formula of a polymeric precursor canbe Cu_(x)(In_(1-y)Ga_(y))_(v)((S_(1-z)Se_(z))R)_(w), where R is asdefined above, x is from 0.5 to 1.5, y is from 0 to 1, z is from 0 to1,v is from 0.5 to 1.5, and w is from 2 to 6.

In some embodiments, the empirical formula of a polymeric precursor canbe Cu_(x)(In_(1-y)Ga_(y))_(v)((S_(1-z)Se_(z))R)_(w), where R is asdefined above, x is from 0.7 to 1.2, y is from 0 to 1, z is from 0 to1,v is from 0.7 to 1.2, and w is from 2 to 6.

In some embodiments, the empirical formula of a polymeric precursor canbe Cu_(x)(In_(1-y)Ga_(y))_(v)((S_(1-z)Se_(z))R)_(w), where R is asdefined above, x is from 0.8 to 1, y is from 0 to 1, z is from 0 to 1, vis from 0.8 to 1.1, and w is from 2 to 6.

In some embodiments, the empirical formula of a polymeric precursor canbe Cu_(x)(In_(1-y)Ga_(y))_(v)((S_(1-z)Se_(z))R)_(w), where R is asdefined above, x is from 0.8 to 0.95, y is from 0 to 1, z is from 0 to1, v is from 0.95 to 1.05, and w is from 3.6 to 4.4.

In further aspects, a mixture of polymeric precursor compounds mayadvantageously be prepared with any desired stoichiometry with respectto the number of different Group 13 elements and their respectiveratios.

As shown in Reaction Scheme 12, a polymeric precursor compound may beprepared by contacting x equivalents of M^(B1)(ER¹)₃, y equivalents ofM^(B2)(ER²)₃, and z equivalents of M^(A)(ER³), where M^(B1) and M^(B2)are different atoms of Group 13, x is from 0.5 to 1.5, y is from 0.5 to1.5, and z is from 0.5 to 1.5. A polymeric precursor compound may havethe empirical formula Cu_(x)In_(y)Ga_(z)(ER¹)_(x)(ER²)_(3y)(ER³)_(3z),where R¹, R² and R³ are the same or each different from each other.

Crosslinking Polymeric Precursors

Embodiments of this invention encompass methods and compositions forcrosslinking polymeric precursors and compositions.

In some aspects, a crosslinked polymeric precursor may be used tocontrol the viscosity of a precursor composition or a polymericprecursor ink composition. The crosslinking of a polymeric precursor canincrease its molecular weight. The molecular weight of a polymericprecursor can be varied over a wide range by incorporating crosslinkinginto the preparation of the precursor. The viscosity of an inkcomposition can be varied over a wide range by using a crosslinkedprecursor to prepare an ink composition.

In some embodiments, the crosslinking of a polymeric precursorcomposition may be used to control the viscosity of the composition orof a polymeric precursor ink composition. A polymeric precursorcomponent of a composition can be crosslinked by adding a crosslinkingagent to the composition. The viscosity of an ink composition may bevaried over a wide range by adding a crosslinking agent to the inkcomposition.

In further aspects, the crosslinking of a polymeric precursorcomposition may be used to control the variation of properties of thinfilms made with the precursor.

Examples of a crosslinking agent include E(Si(CH₃)₃)₂, where E is asdefined above, which can link polymer chains via an M-E-M crosslink.

Examples of a crosslinking agent include HEREH, M^(A)(ERE)H andM^(A)(ERE)M^(A), where M^(A), E, and R are as defined above.

A crosslinking agent can be made by reacting Cu₂O with HEREH to formCu(ERE)H or Cu(ERE)Cu.

Examples of a crosslinking agent include dithiols and diselenols, forexample, HER′EH, where E and R are as defined above. A diselenol canreact with two ER groups of different polymeric precursor chains to linkthe chains together.

An example of crosslinking using HER′EH is shown in Reaction Scheme 14.In Reaction Scheme 14, two chains of a polymeric precursor are linked bythe diselenol with elimination of 2HER.

In another example, Cu(ER′E)Cu can be used during synthesis of apolymeric precursor to form crosslinks.

Embodiments of this invention may further provide a crosslinking agenthaving the formula (RE)₂M¹³(ER′E)M¹³(ER)₂, where M¹³, E, R′ and R are asdefined above. A crosslinking agent of this kind may be used eitherduring synthesis of a polymeric precursor to form crosslinks, or information of an ink or other composition.

In some embodiments, a polymeric precursor may incorporate crosslinkablefunctional groups. A crosslinkable functional group may be attached to aportion of the R groups of one or more kinds in the polymeric precursor.

Examples of crosslinkable functional groups include vinyl,vinylacrylate, epoxy, and cycloaddition and Diels-Alder reactive pairs.Crosslinking may be performed by methods known in the art including theuse of heat, light or a catalyst, as well as by vulcanization withelemental sulfur.

Dopants

In some embodiments, a polymeric precursor composition may include adopant. A dopant may be introduced into a polymeric precursor in thesynthesis of the precursor, or alternatively, can be added to acomposition or ink containing the polymeric precursor. A semiconductormaterial or thin film of this disclosure made from a polymeric precursormay contain atoms of one or more dopants. Methods for introducing adopant into a photovoltaic absorber layer include preparing the absorberlayer with a polymeric precursor of this invention containing thedopant.

The quantity of a dopant in an embodiment of this disclosure can be fromabout 1×10⁻⁷ atom percent to about 5 atom percent relative to the mostabundant Group 11 atom, or greater. In some embodiments, a dopant can beincluded at a level of from about 1×10¹⁶ cm⁻³ to about 1×10²¹ cm⁻³. Adopant can be included at a level of from about 1 ppm to about 10,000ppm.

In some embodiments, a dopant may be an alkali metal atom including Li,Na, K, Rb, and a mixture of any of the foregoing.

Embodiments of this invention may further include a dopant being analkaline earth metal atom including Be, Mg, Ca, Sr, Ba, and a mixture ofany of the foregoing.

In some embodiments, a dopant may be a transition metal atom from Group3 through Group 12, including W, Ni, Pd, Pt, Zn, Cd, Hg, and a mixtureof any of the foregoing.

A dopant of this disclosure may be a main group atom including C, Si,Ge, Sn, Pb, P, As, Sb, Bi, and a mixture of any of the foregoing.

In some aspects, a polymeric precursor composition may advantageously beprepared to incorporate alkali metal ions as dopants.

For example, a polymeric precursor composition may be prepared using anamount of Na(ER), where E is S or Se and R is alkyl or aryl. In certainembodiments, a polymeric precursor composition may be prepared using anamount of NaIn(ER)₄, NaGa(ER)₄, LiIn(ER)₄, LiGa(ER)₄, KIn(ER)₄,KGa(ER)₄, or mixtures thereof, where E is S or Se and R is alkyl oraryl. A polymeric precursor compound of this kind can be used to controlthe level of alkali metal ions.

A dopant may be provided in a precursor as a counterion or introducedinto a thin film by any of the deposition methods described herein. Adopant may also be introduced into a thin film by methods known in theart including ion implantation.

A dopant of this disclosure may be p-type or n-type.

Any of the foregoing dopants may be used in an ink of this invention.

Capping Compounds

In some embodiments, a polymeric precursor composition may be formed asshown in Reaction Schemes 1 through 6, where one or more cappingcompounds are added to the reactions. A capping compound may control theextent of polymer chain formation. A capping compound may also be usedto control the viscosity of an ink containing the polymeric precursorcompound or composition, as well as its solubility and ability to from asuspension. Examples of capping compounds include inorganic ororganometallic complexes which bind to repeating units A or B, or both,and prevent further chain propagation. Examples of capping compoundsinclude R₂M^(B)ER, and RM^(B)(ER)₂.

Ligands

As used herein, the term ligand refers to any atom or chemical moietythat can donate electron density in bonding or coordination.

A ligand can be monodentate, bidentate or multidentate.

As used herein, the term ligand includes Lewis base ligands.

As used herein, the term organic ligand refers to an organic chemicalgroup composed of atoms of carbon and hydrogen, having from 1 to 22carbon atoms, and optionally containing oxygen, nitrogen, sulfur orother atoms, which can bind to another atom or molecule through a carbonatom. An organic ligand can be branched or unbranched, substituted orunsubstituted.

As used herein, the term inorganic ligand refers to an inorganicchemical group which can bind to another atom or molecule through anon-carbon atom.

Examples of ligands include halogens, water, alcohols, ethers,hydroxyls, amides, carboxylates, chalcogenylates, thiocarboxylates,selenocarboxylates, tellurocarboxylates, carbonates, nitrates,phosphates, sulfates, perchlorates, oxalates, and amines.

As used herein, the term chalcogenylate refers to thiocarboxylate,selenocarboxylate, and tellurocarboxylate, having the formula RCE₂ ⁻,where E is S, Se, or Te.

As used herein, the term chalcocarbamate refers to thiocarbamate,selenocarbamate, and tellurocarbamate, having the formula R¹R²NCE₂ ⁻,where E is S, Se, or Te, and R¹ and R² are the same or different and arehydrogen, alkyl, aryl, or an organic ligand.

Examples of ligands include F, Cl⁻, H₂O, ROH, R₂O, OH⁻, RO⁻, NR₂ ⁻, RCO₂⁻, RCE₂ ⁻, CO₃ ²⁻, NO₃ ⁻, PO₄ ³⁻, SO₄ ²⁻, ClO₄ ⁻, C₂O₄ ²⁻, NH₃, NR₃,R₂NH, and RNH₂, where R is alkyl, and E is chalcogen.

Examples of ligands include azides, heteroaryls, thiocyanates,arylamines, arylalkylamines, nitrites, and sulfites.

Examples of ligands include Br⁻, N₃ ⁻, pyridine, [SCN—]⁻, ArNH₂, NO₂ ⁻,and SO₃ ²⁻ where Ar is aryl.

Examples of ligands include cyanides or nitriles, isocyanides orisonitriles, alkylcyanides, alkylnitriles, alkylisocyanides,alkylisonitriles, arylcyanides, arylnitriles, arylisocyanides, andarylisonitriles.

Examples of ligands include hydrides, carbenes, carbon monoxide,isocyanates, isonitriles, thiolates, alkylthiolates, dialkylthiolates,thioethers, thiocarbamates, phosphines, alkylphosphines, arylphosphines,arylalkylphosphines, arsenines, alkylarsenines, arylarsenines,arylalkylarsenines, stilbines, alkylstilbines, arylstilbines, andarylalkylstilbines.

Examples of ligands include I⁻, H⁻, R⁻, —CN⁻, —CO, RNC, RSH, R₂S, RS⁻,—SCN⁻, R₃P, R₃As, R₃Sb, alkenes, and aryls, where each R isindependently alkyl, aryl, or heteroaryl.

Examples of ligands include trioctylphosphine, trimethylvinylsilane andhexafluoroacetylacetonate.

Examples of ligands include nitric oxide, silyls, alkylgermyls,arylgermyls, arylalkylgermyls, alkylstannyls, arylstannyls,arylalkylstannyls, selenocyanates, selenolates, alkylselenolates,dialkylselenolates, selenoethers, selenocarbamates, tellurocyanates,tellurolates, alkyltellurolates, dialkyltellurolates, telluroethers, andtellurocarbamates.

Examples of ligands include chalcogenates, thiothiolates,selenothiolates, thioselenolates, selenoselenolates, alkylthiothiolates, alkyl selenothiolates, alkyl thioselenolates, alkylselenoselenolates, aryl thiothiolates, aryl selenothiolates, arylthioselenolates, aryl selenoselenolates, arylalkyl thiothiolates,arylalkyl selenothiolates, arylalkyl thioselenolates, and arylalkylselenoselenolates.

Examples of ligands include selenoethers and telluroethers.

Examples of ligands include NO, O²⁻, NH_(n)R_(3-n), PH_(n)R_(3-n), SiR₃⁻, GeR₃ ⁻, SnR₃ ⁻, ⁻SR, ⁻SeR, ⁻TeR, ⁻SSR, ⁻SeSR, ⁻SSeR, ⁻SeSeR, and RCN,where n is from 1 to 3, and each R is independently alkyl or aryl.

As used herein, the term transition metals refers to atoms of Groups 3though 12 of the Periodic Table of the elements recommended by theCommission on the Nomenclature of Inorganic Chemistry and published inIUPAC Nomenclature of Inorganic Chemistry, Recommendations 2005.

Photovoltaic Absorber Layer Compositions

A polymeric precursor may be used to prepare a material for use indeveloping semiconductor products.

The polymeric precursors of this invention may advantageously be used inmixtures to prepare a material with controlled or predeterminedstoichiometric ratios of the metal atoms in the material.

In some aspects, processes for solar cells that avoid additionalsulfurization or selenization steps may advantageously use polymericprecursor compounds and compositions of this invention.

A polymeric precursor may be used to prepare an absorber material for asolar cell product. The absorber material may have the empirical formulaM^(A) _(x)(M^(B) _(1-y)M^(C) _(y))_(v)(E¹ _(1-z)E² _(z))_(w), whereM^(A) is a Group 11 atom of Cu, M^(B) and M^(c) are different Group 13atoms selected from Ga and In, when E¹ is S then E² is Se or Te, or whenE¹ is Te then E² is Se, x is from 0.5 to 1.5, y is from 0 to 1, and z isfrom 0 to 1, v is from 0.5 to 1.5, and w is from 1.5 to 2.5.

The absorber material may be either an n-type or a p-type semiconductor,when such compound is known to exist.

In some embodiments, one or more polymeric precursor compounds may beused to prepare a CIS layer on a substrate, wherein the layer has theempirical formula Cu_(x)In_(y)(S_(1-z)Se_(z))_(w), where x is from 0.5to 1.5, y is from 0.5 to 1.5, z is from 0 to 1, and w is from 1.5 to2.5.

In some aspects, one or more polymeric precursor compounds may be usedto prepare a CIS layer on a substrate, wherein the layer has theempirical formula Cu_(x)In_(y)(S_(1-z)Se_(z))_(w), where x is from 0.7to 1.1, y is from 0.7 to 1.1, z is from 0 to 1, and w is from 1.5 to2.5.

In certain embodiments, one or more polymeric precursor compounds may beused to prepare a CIS layer on a substrate, wherein the layer has theempirical formula Cu_(x)In_(y)(S_(1-z)Se_(z))_(w), where x is from 0.8to 0.95, y is from 0.95 to 1.05, z is from 0 to 1, and w is from 1.8 to2.2.

In some embodiments, one or more polymeric precursor compounds may beused to prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.5 to 1.5, y is from 0 to 1, and z is from 0 to 1, v is from0.5 to 1.5, and w is from 1.5 to 2.5.

In some aspects, one or more polymeric precursor compounds may be usedto prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.7 to 1.2, y is from 0 to 1, and z is from 0 to 1, v is from0.7 to 1.2, and w is from 1.5 to 2.5.

In some variations, one or more polymeric precursor compounds may beused to prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.7 to 1.1, y is from 0 to 1, and z is from 0 to 1, v is from0.7 to 1.1, and w is from 1.5 to 2.5.

In certain embodiments, one or more polymeric precursor compounds may beused to prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.7 to 1.1, y is from 0 to 1, and z is from 0.5 to 1, v is from0.7 to 1.1, and w is from 1.5 to 2.5.

In certain embodiments, one or more polymeric precursor compounds may beused to prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.8 to 0.95, y is from 0.5 to 1, and z is from 0.5 to 1, v isfrom 0.95 to 1.05, and w is from 1.8 to 2.2.

In certain embodiments, one or more polymeric precursor compounds may beused to prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.8 to 0.95, y is from 0.5 to 1, and z is from 0.5 to 1, v isfrom 0.95 to 1.05, and w is from 2.0 to 2.2.

Embodiments of this invention may further provide polymeric precursorsthat can be used to prepare a CIS or CIGS material for a solar cellproduct.

In some aspects, one or more polymeric precursors may be used to preparea CIS or CIGS material as a chemically and physically uniform layer.

In some variations, one or more polymeric precursors may be used toprepare a CIS or CIGS material wherein the stoichiometry of the metalatoms of the CIGS material can be controlled.

In certain variations, one or more polymeric precursors may be used toprepare a CIS or CIGS material using nanoparticles prepared with thepolymeric precursors.

In certain embodiments, one or more polymeric precursors may be used toprepare a CIS or CIGS material as a layer that may be processed atrelatively low temperatures to achieve a solar cell.

In some aspects, one or more polymeric precursors may be used to preparea CIS or CIGS material as a photovoltaic layer.

In some variations, one or more polymeric precursors may be used toprepare a chemically and physically uniform semiconductor CIS or CIGSlayer on a variety of substrates, including flexible substrates.

Examples of an absorber material include CuGaS₂, AgGaS₂, AuGaS₂, CuInS₂,AgInS₂, AuInS₂, CuTlS₂, AgTlS₂, AuTlS₂, CuGaSe₂, AgGaSe₂, AuGaSe₂,CuInSe₂, AgInSe₂, AuInSe₂, CuTlSe₂, AgTlSe₂, AuTlSe₂, CuGaTe₂, AgGaTe₂,AuGaTe₂, CuInTe₂, AgInTe₂, AuInTe₂, CuTlTe₂, AgTlTe₂, and AuTlTe₂.

Examples of an absorber material include CuInGaSSe, AgInGaSSe,AuInGaSSe, CuInTlSSe, AgInTlSSe, AuInTlSSe, CuGaTlSSe, AgGaTlSSe,AuGaTlSSe, CuInGaSSe, AgInGaSeTe, AuInGaSeTe, CuInTlSeTe, AgInTlSeTe,AuInTlSeTe, CuGaTlSeTe, AgGaTlSeTe, AuGaTlSeTe, CuInGaSTe, AgInGaSTe,AuInGaSTe, CuInTlSTe, AgInTlSTe, AuInTlSTe, CuGaTlSTe, AgGaTlSTe, andAuGaTlSTe.

The CIS or CIGS layer may be used with various junction partners toproduce a solar cell. Examples of junction partner layers are known inthe art and include CdS, ZnS, ZnSe, and CdZnS. See, for example, MartinGreen, Solar Cells: Operating Principles, Technology and SystemApplications (1986); Richard H. Bube, Photovoltaic Materials (1998);Antonio Luque and Steven Hegedus, Handbook of Photovoltaic Science andEngineering (2003).

In some aspects, the thickness of an absorber layer may be from about0.001 to about 100 micrometers, or from about 0.001 to about 20micrometers, or from about 0.01 to about 10 micrometers, or from about0.05 to about 5 micrometers, or from about 0.1 to about 4 micrometers,or from about 0.1 to about 3.5 micrometers, or from about 0.1 to about 3micrometers, or from about 0.1 to about 2.5 micrometers.

Substrates

The polymeric precursors of this invention can be used to form a layeron a substrate. The substrate can be made of any substance, and can haveany shape.

Substrate layers of polymeric precursors can be used to create aphotovoltaic layer or device.

Examples of substrates on which a polymeric precursor of this disclosurecan be deposited or printed include semiconductors, dopedsemiconductors, silicon, gallium arsenide, insulators, glass, molybdenumglass, silicon dioxide, titanium dioxide, zinc oxide, silicon nitride,and combinations thereof.

A substrate may be coated with molybdenum or a molybdenum-containingcompound.

In some embodiments, a substrate may be pre-treated with amolybdenum-containing compound, or one or more compounds containingmolybdenum and selenium.

Examples of substrates on which a polymeric precursor of this disclosurecan be deposited or printed include metals, metal foils, molybdenum,aluminum, beryllium, cadmium, cerium, chromium, cobalt, copper, gallium,gold, lead, manganese, nickel, palladium, platinum, rhenium, rhodium,silver, stainless steel, steel, iron, strontium, tin, titanium,tungsten, zinc, zirconium, metal alloys, metal silicides, metalcarbides, and combinations thereof.

Examples of substrates on which a polymeric precursor of this disclosurecan be deposited or printed include polymers, plastics, conductivepolymers, copolymers, polymer blends, polyethylene terephthalates,polycarbonates, polyesters, polyester films, mylars, polyvinylfluorides, polyvinylidene fluoride, polyethylenes, polyetherimides,polyethersulfones, polyetherketones, polyimides, polyvinylchlorides,acrylonitrile butadiene styrene polymers, silicones, epoxys, andcombinations thereof.

Examples of substrates on which a polymeric precursor of this disclosurecan be deposited or printed include roofing materials.

Examples of substrates on which a polymeric precursor of this disclosurecan be deposited or printed include papers and coated papers.

A substrate of this disclosure can be of any shape. Examples ofsubstrates on which a polymeric precursor of this disclosure can bedeposited include a shaped substrate including a tube, a cylinder, aroller, a rod, a pin, a shaft, a plane, a plate, a blade, a vane, acurved surface or a spheroid.

A substrate may be layered with an adhesion promoter before thedeposition, coating or printing of a layer of a polymeric precursor ofthis invention.

Examples of adhesion promoters include a glass layer, a metal layer, atitanium-containing layer, a tungsten-containing layer, atantalum-containing layer, tungsten nitride, tantalum nitride, titaniumnitride, titanium nitride silicide, tantalum nitride silicide, achromium-containing layer, a vanadium-containing layer, a nitride layer,an oxide layer, a carbide layer, and combinations thereof.

Examples of adhesion promoters include organic adhesion promoters suchas organofunctional silane coupling agents, silanes,hexamethyldisilazanes, glycol ether acetates, ethylene glycolbis-thioglycolates, acrylates, acrylics, mercaptans, thiols, selenols,tellurols, carboxylic acids, organic phosphoric acids, triazoles, andmixtures thereof.

Substrates may be layered with a barrier layer before the deposition ofprinting of a layer of a polymeric precursor of this invention.

Examples of a barrier layer include a glass layer, a metal layer, atitanium-containing layer, a tungsten-containing layer, atantalum-containing layer, tungsten nitride, tantalum nitride, titaniumnitride, titanium nitride silicide, tantalum nitride silicide, andcombinations thereof.

A substrate can be of any thickness, and can be from about 20micrometers to about 20,000 micrometers or more in thickness.

Ink Compositions

Embodiments of this invention further provide ink compositions whichcontain one or more polymeric precursor compounds. The polymericprecursors of this invention may be used to make photovoltaic materialsby printing an ink onto a substrate.

An ink of this disclosure advantageously allows precise control of thestoichiometric ratios of certain atoms in the ink because the ink can becomposed of a mixture of polymeric precursors.

Inks of this disclosure can be made by any methods known in the art.

In some embodiments, an ink can be made by mixing a polymeric precursorwith one or more carriers. The ink may be a suspension of the polymericprecursors in an organic carrier. In some variations, the ink is asolution of the polymeric precursors in an organic carrier. The carriercan be an organic liquid.

An ink can be made by providing one or more polymeric precursorcompounds and solubilizing, dissolving, solvating, or dispersing thecompounds with one or more carriers. The compounds dispersed in acarrier may be nanocrystalline, nanoparticles, microparticles,amorphous, or dissolved molecules.

The concentration of the polymeric precursors in an ink of thisdisclosure can be from about 0.001% to about 99% (w/w), or from about0.001% to about 90%, or from about 0.1% to about 90%.

A polymeric precursor may exist in a liquid or flowable phase under thetemperature and conditions used for deposition, coating or printing.

In some variations of this invention, polymeric precursors that arepartially soluble, or are insoluble in a particular carrier can bedispersed in the carrier by high shear mixing.

As used herein, the term dispersing encompasses the terms solubilizing,dissolving, and solvating.

The carrier for an ink of this disclosure may be an organic liquid orsolvent. Examples of a carrier for an ink of this disclosure include oneor more organic solvents, which may contain an aqueous component.

Embodiments of this invention further provide polymeric precursorcompounds having enhanced solubility in one or more carriers forpreparing inks The solubility of a polymeric precursor compound can beselected by variation of the nature and molecular size and weight of oneor more organic ligands attached to the compound.

An ink composition of this invention may contain any of the dopantsdisclosed herein, or a dopant known in the art.

Ink compositions of this disclosure can be made by methods known in theart, as well as methods disclosed herein.

Examples of a carrier for an ink of this disclosure include alcohol,methanol, ethanol, isopropyl alcohol, thiols, butanol, butanediol,glycerols, alkoxyalcohols, glycols, 1-methoxy-2-propanol, acetone,ethylene glycol, propylene glycol, propylene glycol laurate, ethyleneglycol ethers, diethylene glycol, triethylene glycol monobutylether,propylene glycol monomethylether, 1,2-hexanediol, ethers, diethyl ether,aliphatic hydrocarbons, aromatic hydrocarbons, pentane, hexane, heptane,octane, isooctane, decane, cyclohexane, p-xylene, m-xylene, o-xylene,benzene, toluene, xylene, tetrahydrofuran, 2-methyltetrahydrofuran,siloxanes, cyclosiloxanes, silicone fluids, halogenated hydrocarbons,dibromomethane, dichloromethane, dichloroethane, trichloroethanechloroform, methylene chloride, acetonitrile, esters, acetates, ethylacetate, butyl acetate, acrylates, isobornyl acrylate, 1,6-hexanedioldiacrylate, polyethylene glycol diacrylate, ketones, acetone, methylethyl ketone, cyclohexanone, butyl carbitol, cyclopentanone, lactams,N-methylpyrrolidone, N-(2-hydroxyethyl)-pyrrolidone, cyclic acetals,cyclic ketals, aldehydes, amides, dimethylformamide, methyl lactate,oils, natural oils, terpenes, and mixtures thereof.

An ink of this disclosure may further include components such as asurfactant, a dispersant, an emulsifier, an anti-foaming agent, a dryer,a filler, a resin binder, a thickener, a viscosity modifier, ananti-oxidant, a flow agent, a plasticizer, a conductivity agent, acrystallization promoter, an extender, a film conditioner, an adhesionpromoter, and a dye. Each of these components may be used in an ink ofthis disclosure at a level of from about 0.001% to about 10% or more ofthe ink composition.

Examples of surfactants include siloxanes, polyalkyleneoxide siloxanes,polyalkyleneoxide polydimethylsiloxanes, polyesterpolydimethylsiloxanes, ethoxylated nonylphenols, nonylphenoxypolyethyleneoxyethanol, fluorocarbon esters, fluoroaliphatic polymericesters, fluorinated esters, alkylphenoxy alkyleneoxides, cetyl trimethylammonium chloride, carboxymethylamylose, ethoxylated acetylene glycols,betaines, N-n-dodecyl-N,N-dimethylbetaine, dialkyl sulfosuccinate salts,alkylnaphthalenesulfonate salts, fatty acid salts, polyoxyethylenealkylethers, polyoxyethylene alkylallylethers,polyoxyethylene-polyoxypropylene block copolymers, alkylamine salts,quaternary ammonium salts, and mixtures thereof.

Examples of surfactants include anionic, cationic, amphoteric, andnonionic surfactants. Examples of surfactants include SURFYNOL, DYNOL,ZONYL, FLUORAD, and SILWET surfactants.

A surfactant may be used in an ink of this disclosure at a level of fromabout 0.001% to about 2% of the ink composition.

Examples of a dispersant include a polymer dispersant, a surfactant,hydrophilic-hydrophobic block copolymers, acrylic block copolymers,acrylate block copolymers, graft polymers, and mixtures thereof.

Examples of an emulsifier include a fatty acid derivative, an ethylenestearamide, an oxidized polyethylene wax, mineral oils, apolyoxyethylene alkyl phenol ether, a polyoxyethylene glycol ether blockcopolymer, a polyoxyethylene sorbitan fatty acid ester, a sorbitan, analkyl siloxane polyether polymer, polyoxyethylene monostearates,polyoxyethylene monolaurates, polyoxyethylene monooleates, and mixturesthereof.

Examples of an anti-foaming agent include polysiloxanes,dimethylpolysiloxanes, dimethyl siloxanes, silicones, polyethers, octylalcohol, organic esters, ethyleneoxide propyleneoxide copolymers, andmixtures thereof.

Examples of a dryer include aromatic sulfonic acids, aromatic carboxylicacids, phthalic acid, hydroxyisophthalic acid, N-phthaloylglycine,2-pyrrolidone 5-carboxylic acid, and mixtures thereof.

Examples of a filler include metallic fillers, silver powder, silverflake, metal coated glass spheres, graphite powder, carbon black,conductive metal oxides, ethylene vinyl acetate polymers, and mixturesthereof.

Examples of a resin binder include acrylic resins, alkyd resins, vinylresins, polyvinyl pyrrolidone, phenolic resins, ketone resins, aldehyderesins, polyvinyl butyral resin, amide resins, amino resins,acrylonitrile resins, cellulose resins, nitrocellulose resins, rubbers,fatty acids, epoxy resins, ethylene acrylic copolymers, fluoropolymers,gels, glycols, hydrocarbons, maleic resins, urea resins, naturalrubbers, natural gums, phenolic resins, cresols, polyamides,polybutadienes, polyesters, polyolefins, polyurethanes, isocynates,polyols, thermoplastics, silicates, silicones, polystyrenes, andmixtures thereof.

Examples of thickeners and viscosity modifiers include conductingpolymers, celluloses, urethanes, polyurethanes, styrene maleic anhydridecopolymers, polyacrylates, polycarboxylic acids, carboxymethylcelluoses,hydroxyethylcelluloses, methylcelluloses, methyl hydroxyethylcelluloses, methyl hydroxypropyl celluloses, silicas, gellants,aluminates, titanates, gums, clays, waxes, polysaccharides, starches,and mixtures thereof.

Examples of anti-oxidants include phenolics, phosphites, phosphonites,thioesters, stearic acids, ascorbic acids, catechins, cholines, andmixtures thereof.

Examples of flow agents include waxes, celluloses, butyrates,surfactants, polyacrylates, and silicones.

Examples of a plasticizer include alkyl benzyl phthalates, butyl benzylphthalates, dioctyl phthalates, diethyl phthalates, dimethyl phthalates,di-2-ethylhexy-adipates, diisobutyl phthalates, diisobutyl adipates,dicyclohexyl phthalates, glycerol tribenzoates, sucrose benzoates,polypropylene glycol dibenzoates, neopentyl glycol dibenzoates, dimethylisophthalates, dibutyl phthalates, dibutyl sebacates,tri-n-hexyltrimellitates, and mixtures thereof.

Examples of a conductivity agent include lithium salts, lithiumtrifluoromethanesulfonates, lithium nitrates, dimethylaminehydrochlorides, diethylamine hydrochlorides, hydroxylaminehydrochlorides, and mixtures thereof.

Examples of a crystallization promoter include copper chalcogenides,alkali metal chalcogenides, alkali metal salts, alkaline earth metalsalts, sodium chalcogenates, cadmium salts, cadmium sulfates, cadmiumsulfides, cadmium selenides, cadmium tellurides, indium sulfides, indiumselenides, indium tellurides, gallium sulfides, gallium selenides,gallium tellurides, molybdenum, molybdenum sulfides, molybdenumselenides, molybdenum tellurides, molybdenum-containing compounds, andmixtures thereof.

An ink may contain one or more components selected from the group of aconducting polymer, copper metal, indium metal, gallium metal, zincmetal, alkali metals, alkali metal salts, alkaline earth metal salts,sodium chalcogenates, calcium chalcogenates, cadmium sulfide, cadmiumselenide, cadmium telluride, indium sulfide, indium selenide, indiumtelluride, gallium sulfide, gallium selenide, gallium telluride, zincsulfide, zinc selenide, zinc telluride, copper sulfide, copper selenide,copper telluride, molybdenum sulfide, molybdenum selenide, molybdenumtelluride, and mixtures of any of the foregoing.

An ink of this disclosure may contain particles of a metal, a conductivemetal, or an oxide. Examples of metal and oxide particles includesilica, alumina, titania, copper, iron, steel, aluminum and mixturesthereof.

In certain variations, an ink may contain a biocide, a sequesteringagent, a chelator, a humectant, a coalescent, or a viscosity modifier.

In certain aspects, an ink of this disclosure may be formed as asolution, a suspension, a slurry, or a semisolid gel or paste. An inkmay include one or more polymeric precursors solubilized in a carrier,or may be a solution of the polymeric precursors. In certain variations,a polymeric precursor may include particles or nanoparticles that can besuspended in a carrier, and may be a suspension or paint of thepolymeric precursors. In certain embodiments, a polymeric precursor canbe mixed with a minimal amount of a carrier, and may be a slurry orsemisolid gel or paste of the polymeric precursor.

The viscosity of an ink of this disclosure can be from about 0.5centipoises (cP) to about 50 cP, or from about 0.6 to about 30 cP, orfrom about 1 to about 15 cP, or from about 2 to about 12 cP.

The viscosity of an ink of this disclosure can be from about 20 cP toabout 2×10⁶ cP, or greater. The viscosity of an ink of this disclosurecan be from about 20 cP to about 1×10⁶ cP, or from about 200 cP to about200,000 cP, or from about 200 cP to about 100,000 cP, or from about 200cP to about 40,000 cP, or from about 200 cP to about 20,000 cP.

The viscosity of an ink of this disclosure can be about 1 cP, or about 2cP, or about 5 cP, or about 20 cP, or about 100 cP, or about 500 cP, orabout 1,000 cP, or about 5,000 cP, or about 10,000 cP, or about 20,000cP, or about 30,000 cP, or about 40,000 cP.

In some embodiments, an ink may contain one or more components from thegroup of a surfactant, a dispersant, an emulsifier, an anti-foamingagent, a dryer, a filler, a resin binder, a thickener, a viscositymodifier, an anti-oxidant, a flow agent, a plasticizer, a conductivityagent, a crystallization promoter, an extender, a film conditioner, anadhesion promoter, and a dye. In certain variations, an ink may containone or more compounds from the group of cadmium sulfide, cadmiumselenide, cadmium telluride, zinc sulfide, zinc selenide, zinctelluride, copper sulfide, copper selenide, and copper telluride. Insome aspects, an ink may contain particles of a metal, a conductivemetal, or an oxide.

An ink may be made by dispersing one or more polymeric precursorcompounds of this disclosure in one or more carriers to form adispersion or solution.

A polymeric precursor ink composition can be prepared by dispersing oneor more polymeric precursors in a solvent, and heating the solvent todissolve or disperse the polymeric precursors. The polymeric precursorsmay have a concentration of from about 0.001% to about 99% (w/w), orfrom about 0.001% to about 90%, or from about 0.1% to about 90%, or fromabout 0.1% to about 50%, or from about 0.1% to about 40%, or from about0.1% to about 30%, or from about 0.1% to about 20%, or from about 0.1%to about 10% in the solution or dispersion.

Processes for Films of Polymeric Precursors on Substrates

The polymeric precursors of this invention can be used to makephotovoltaic materials by depositing a layer onto a substrate, where thelayer contains one or more polymeric precursors. The deposited layer maybe a film or a thin film. Substrates are described above.

As used herein, the terms “deposit,” “depositing,” and “deposition”refer to any method for placing a compound or composition onto a surfaceor substrate, including spraying, coating, and printing.

As used herein, the term “thin film” refers to a layer of atoms ormolecules, or a composition layer on a substrate having a thickness ofless than about 300 micrometers.

A deposited layer of this disclosure advantageously allows precisecontrol of the stoichiometric ratios of certain atoms in the layerbecause the layer can be composed of a mixture of polymeric precursors.

The polymeric precursors of this invention, and compositions containingpolymeric precursors, can be deposited onto a substrate using methodsknown in the art, as well as methods disclosed herein.

Examples of methods for depositing a polymeric precursor onto a surfaceor substrate include all forms of spraying, coating, and printing.

Solar cell layers can be made by depositing one or more polymericprecursors of this disclosure on a flexible substrate in a highthroughput roll process. The depositing of polymeric precursors in ahigh throughput roll process can be done by spraying or coating acomposition containing one or more polymeric precursors, or by printingan ink containing one or more polymeric precursors of this disclosure.

Examples of methods for depositing a polymeric precursor onto a surfaceor substrate include spraying, spray coating, spray deposition, spraypyrolysis, and combinations thereof.

Examples of methods for printing using an ink of this disclosure includescreen printing, inkjet printing, aerosol jet printing, ink printing,jet printing, stamp/pad printing, transfer printing, pad printing,flexographic printing, gravure printing, contact printing, reverseprinting, thermal printing, lithography, electrophotographic printing,and combinations thereof.

Examples of methods for depositing a polymeric precursor onto a surfaceor substrate include electrodepositing, electroplating, electrolessplating, bath deposition, coating, dip coating, wet coating, spincoating, knife coating, roller coating, rod coating, slot die coating,meyerbar coating, lip direct coating, capillary coating, liquiddeposition, solution deposition, layer-by-layer deposition, spincasting, and solution casting.

In some embodiments, examples of methods for depositing a polymericprecursor onto a surface or substrate include chemical vapor deposition,aerosol chemical vapor deposition, metal-organic chemical vapordeposition, organometallic chemical vapor deposition, plasma enhancedchemical vapor deposition, and combinations thereof.

Examples of methods for depositing a polymeric precursor onto a surfaceor substrate include atomic layer deposition, plasma-enhanced atomiclayer deposition, vacuum chamber deposition, sputtering, RF sputtering,DC sputtering, magnetron sputtering, evaporation, electron beamevaporation, laser ablation, gas-source polymeric beam epitaxy, vaporphase epitaxy, liquid phase epitaxy, and combinations thereof.

In certain embodiments, a first polymeric precursor may be depositedonto a substrate, and subsequently a second polymeric precursor may bedeposited onto the substrate. In certain embodiments, several differentpolymeric precursors may be deposited onto the substrate to create alayer.

In certain variations, different polymeric precursors may be depositedonto a substrate simultaneously, or sequentially, whether by spraying,coating, printing, or by other methods. The different polymericprecursors may be contacted or mixed before the depositing step, duringthe depositing step, or after the depositing step. The polymericprecursors can be contacted before, during, or after the step oftransporting the polymeric precursors to the substrate surface.

The depositing of polymeric precursors, including by spraying, coating,and printing, can be done in a controlled or inert atmosphere, such asin dry nitrogen and other inert gas atmospheres, as well as in a partialvacuum atmosphere.

Processes for depositing, spraying, coating, or printing polymericprecursors can be done at various temperatures including from about −20°C. to about 650° C., or from about −20° C. to about 600° C., or fromabout −20° C. to about 400° C., or from about 20° C. to about 360° C.,or from about 20° C. to about 300° C., or from about 20° C. to about250° C.

Processes for making a solar cell involving a step of transforming apolymeric precursor compound into a material or semiconductor can beperformed at various temperatures including from about 100° C. to about650° C., or from about 150° C. to about 650° C., or from about 250° C.to about 650° C., or from about 300° C. to about 650° C., or from about400° C. to about 650° C.

In certain aspects, depositing of polymeric precursors on a substratecan be done while the substrate is heated. In these variations, athin-film material may be deposited or formed on the substrate.

In some embodiments, a step of converting a precursor to a material anda step of annealing can be done simultaneously. In general, a step ofheating a precursor can be done before, during or after any step ofdepositing the precursor.

In some variations, a substrate can be cooled after a step of heating.In certain embodiments, a substrate can be cooled before, during, orafter a step of depositing a precursor. A substrate may be cooled toreturn the substrate to a lower temperature, or to room temperature, orto an operating temperature of a deposition unit. Various coolants orcooling methods can be applied to cool a substrate.

The depositing of polymeric precursors on a substrate may be done withvarious apparatuses and devices known in art, as well as devicesdescribed herein.

In some variations, the depositing of polymeric precursors can beperformed using a spray nozzle with adjustable nozzle dimensions toprovide a uniform spray composition and distribution.

Embodiments of this disclosure further contemplate articles made bydepositing a layer onto a substrate, where the layer contains one ormore polymeric precursors. The article may be a substrate having a layerof a film, or a thin film, which is deposited, sprayed, coated, orprinted onto the substrate. In certain variations, an article may have asubstrate printed with a polymeric precursor ink, where the ink isprinted in a pattern on the substrate.

Photovoltaic Devices

The polymeric precursors of this invention can be used to makephotovoltaic materials and solar cells of high efficiency.

As shown in FIG. 6, embodiments of this invention may further provideoptoelectronic devices and energy conversion systems. Following thesynthesis of polymeric precursor compounds, the compounds can besprayed, deposited, or printed onto substrates and formed into absorbermaterials and semiconductor layers. Absorber materials can be the basisfor optoelectronic devices and energy conversion systems.

In some embodiments, the solar cell is a thin layer solar cell having aCIS or CIGS absorber layer deposited or printed on a substrate.

Embodiments of this invention may provide improved efficiency for solarcells used for light to electricity conversion.

In some embodiments, a solar cell of this disclosure is a heterojunctiondevice made with a CIS or CIGS cell. The CIS or CIGS layer may be usedas a junction partner with a layer of, for example, cadmium sulfide,cadmium selenide, cadmium telluride, zinc sulfide, zinc selenide, orzinc telluride. The absorber layer may be adjacent to a layer of MgS,MgSe, MgTe, HgS, HgSe, HgTe, AN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb,InN, InP, InAs, InSb, or combinations thereof.

In certain variations, a solar cell of this disclosure is amultijunction device made with one or more stacked solar cells.

As shown in FIG. 7, a solar cell device of this disclosure may have asubstrate 10, an electrode layer 20, an absorber layer 30, a windowlayer 40, and a transparent conductive layer (TCO) 50. The substrate 10may be metal, plastic, glass, or ceramic. The electrode layer 20 can bea molybdenum-containing layer. The absorber layer 30 may be a CIS orCIGS layer. The window layer 40 may be a cadmium sulfide layer. Thetransparent conductive layer 50 can be an indium tin oxide layer or adoped zinc oxide layer.

A solar cell device of this disclosure may have a substrate, anelectrode layer, an absorber layer, a window layer, an adhesionpromoting layer, a junction partner layer, a transparent layer, atransparent electrode layer, a transparent conductive oxide layer, atransparent conductive polymer layer, a doped conductive polymer layer,an encapsulating layer, an anti-reflective layer, a protective layer, ora protective polymer layer. In certain variations, an absorber layerincludes a plurality of absorber layers.

In certain variations, solar cells may be made by processes usingpolymeric precursor compounds and compositions of this invention thatadvantageously avoid additional sulfurization or selenization steps.

In certain variations, a solar cell device may have amolybdenum-containing layer, or an interfacial molybdenum-containinglayer.

Examples of a protective polymer include silicon rubbers, butyrylplastics, ethylene vinyl acetates, and combinations thereof.

Substrates can be made of a flexible material which can be handled in aroll. The electrode layer may be a thin foil.

Absorber layers of this disclosure can be made by depositing or printinga composition containing nanoparticles onto a substrate, where thenanoparticles can be made with polymeric precursor compounds of thisinvention. In some processes, nanoparticles can be made or formed fromwith polymeric precursor compounds and deposited on a substrate.Deposited nanoparticles can subsequently be transformed by theapplication of heat or energy.

In some embodiments, the absorber layer may be formed from nanoparticlesor semiconductor nanoparticles which have been deposited on a substrateand subsequently transformed by heat or energy.

In some embodiments, a thin film photovoltaic device may have atransparent conductor layer, a buffer layer, a p-type absorber layer, anelectrode layer, and a substrate. The transparent conductor layer may bea transparent conductive oxide (TCO) layer such as a zinc oxide layer,or zinc oxide layer doped with aluminum, or a carbon nanotube layer, ora tin oxide layer, or a tin oxide layer doped with fluorine, or anindium tin oxide layer, or an indium tin oxide layer doped withfluorine, while the buffer layer can be cadmium sulfide, or cadmiumsulfide and high resistivity zinc oxide. The p-type absorber layer canbe a CIGS layer, and the electrode layer can be molybdenum. Thetransparent conductor layer can be up to about 0.5 micrometers inthickness. The buffer layer can also be a cadmium sulfide n-typejunction partner layer. In some embodiments, the buffer layer may be asilicon dioxide, an aluminum oxide, a titanium dioxide, or a boronoxide.

Some examples of transparent conductive oxides are given in K. Ellmer etal., Transparent Conductive Zinc Oxide, Vol. 104, Springer Series inMaterials Science (2008).

In some aspects, a solar cell can include a molybdenum selenideinterface layer, which may be formed using various molybdenum-containingand selenium-containing compounds that can be added to an ink forprinting, or deposited onto a substrate.

A thin film material photovoltaic absorber layer can be made with one ormore polymeric precursors of this invention. For example, a polymericprecursor ink can be sprayed onto a stainless steel substrate using aspray pyrolysis unit in a glovebox in an inert atmosphere. The spraypyrolysis unit may have an ultrasonic nebulizer, precision flow metersfor inert gas carrier, and a tubular quartz reactor in a furnace. Thespray-coated substrate can be heated at a temperature of from about 25°C. to about 650° C. in an inert atmosphere, thereby producing a thinfilm material photovoltaic absorber layer.

In some examples, a thin film material photovoltaic absorber layer canbe made by providing a polymeric precursor ink which is filtered with a0.45 micron filter, or a 0.3 micron filter. The ink can be depositedonto an aluminum substrate using a spin casting unit in a glovebox ininert argon atmosphere. The substrate can be spin coated with thepolymeric precursor ink to a film thickness of about 0.1 to 5 microns.The substrate can be removed and heated at a temperature of from about100° C. to about 600° C. in an inert atmosphere, thereby producing athin film material photovoltaic absorber layer.

In further examples, a thin film material photovoltaic absorber layercan be made by providing a polymeric precursor ink which is filteredwith a 0.45 micron filter, or a 0.3 micron filter. The ink may beprinted onto a polyethylene terephthalate substrate using a inkjetprinter in a glovebox in an inert atmosphere. A film of about 0.1 to 5microns thickness can be deposited on the substrate. The substrate canbe removed and heated at a temperature of from about 100° C. to about600° C. in an inert atmosphere, thereby producing a thin film materialphotovoltaic absorber layer.

In some examples, a solar cell can be made by providing an electrodelayer on a polyethylene terephthalate substrate. A thin film materialphotovoltaic absorber layer can be coated onto the electrode layer asdescribed above. A window layer can be deposited onto the absorberlayer. A transparent conductive oxide layer can be deposited onto thewindow layer, thereby forming an embodiment of a solar cell.

Methods for making a photovoltaic absorber layer on a substrate includeproviding one or more polymeric precursor compounds, providing asubstrate, spraying the compounds onto the substrate, and heating thesubstrate at a temperature of from about 100° C. to about 600° C., or offrom about 100° C. to about 650° C. in an inert atmosphere, therebyproducing a photovoltaic absorber layer having a thickness of from 0.001to 100 micrometers. The spraying can be done in spray coating, spraydeposition, jet deposition, or spray pyrolysis. The substrate may beglass, metal, polymer, plastic, or silicon.

The photovoltaic absorber layer made by the methods of this disclosuremay have an empirical formulaCu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where x is from 0.8 to0.95, y is from 0.5 to 1, and z is from 0.5 to 1, v is from 0.95 to1.05, and w is from 1.8 to 2.2. The photovoltaic absorber layer made bythe methods of this disclosure may have an empirical formula empiricalformula Cu_(x)In_(y)(S_(1-z)Se_(z))_(w), where x is from 0.8 to 0.95, yis from 0.95 to 1.05, z is from 0 to 1, and w is from 1.8 to 2.2.Methods for making a photovoltaic absorber layer can include a step ofsulfurization or selenization.

In certain variations, methods for making a photovoltaic absorber layermay include heating the compounds to a temperature of from about 20° C.to about 400° C. while depositing, spraying, coating, or printing thecompounds onto the substrate.

Methods for making a photovoltaic absorber layer on a substrate includeproviding one or more polymeric precursor compounds, providing asubstrate, depositing the compounds onto the substrate, and heating thesubstrate at a temperature of from about 100° C. to about 600° C., orfrom about 100° C. to about 400° C., or from about 100° C. to about 300°C. in an inert atmosphere, thereby producing a photovoltaic absorberlayer having a thickness of from 0.001 to 100 micrometers. Thedepositing can be done in electrodepositing, electroplating, electrolessplating, bath deposition, liquid deposition, solution deposition,layer-by-layer deposition, spin casting, or solution casting. Thesubstrate may be glass, metal, polymer, plastic, or silicon.

Methods for making a photovoltaic absorber layer on a substrate includeproviding one or more polymeric precursor inks, providing a substrate,printing the inks onto the substrate, and heating the substrate at atemperature of from about 100° C. to about 600° C. in an inertatmosphere, thereby producing a photovoltaic absorber layer having athickness of from 0.001 to 100 micrometers. The printing can be done inscreen printing, inkjet printing, transfer printing, flexographicprinting, or gravure printing. The substrate may be glass, metal,polymer, plastic, or silicon. The method may further include adding tothe ink an additional indium-containing compound, such as In(SeR)₃,wherein R is alkyl or aryl.

Electrical Power Generation and Transmission

This disclosure contemplates methods for producing and deliveringelectrical power. A photovoltaic device of this invention can be used,for example, to convert solar light to electricity which can be providedto a commercial power grid.

As used herein, the term “solar cell” refers to individual solar cell aswell as a solar cell array, which can combine a number of solar cells.

The solar cell devices of this disclosure can have improved reliability.Solar cell devices can be manufactured in modular panels.

The power systems of this disclosure can be made in large or smallscale, including power for a personal use, as well as on a megawattscale for a public use.

An important feature of the solar cell devices and power systems of thisdisclosure is that they can be manufactured and used with lowenvironmental impact.

A power system of this disclosure may utilize a solar cell on a movablemounting, which may be motorized to face the solar cell toward thelight. Alternatively, a solar cell may be mounted on a fixed object inan optimal orientation.

Solar cells can be attached in panels in which various groups of cellsare electrically connected in series and in parallel to provide suitablevoltage and current characteristics.

Solar cells can be installed on rooftops, as well as outdoor, sunlightedsurfaces of all kinds Solar cells can be combined with various kinds ofroofing materials such as roofing tiles or shingles.

A power system can include a solar cell array and a battery storagesystem. A power system may have a diode-containing circuit and avoltage-regulating circuit to prevent the battery storage system fromdraining through the solar cells or from being overcharged.

A power system can be used to provide power for lighting, electricvehicles, electric buses, electric airplanes, pumping water,desalinization of water, refrigeration, milling, manufacturing, andother uses.

Sources of Elements

Sources of copper include copper metal, Cu(I), Cu(II), copper halides,copper chlorides, copper acetates, copper alkoxides, copper alkyls,copper diketonates, copper 2,2,6,6,-tetramethyl-3,5,-heptanedionate,copper 2,4-pentanedionate, copper hexafluoroacetylacetonate, copperacetylacetonate, copper dimethylaminoethoxide, copper ketoesters, andmixtures thereof.

Sources of indium include indium metal, trialkylindium,trisdialkylamineindium, indium halides, indium chlorides, dimethylindiumchlorides, trimethylindium, indium acetylacetonates, indiumhexafluoropentanedionates, indium methoxyethoxides, indiummethyltrimethylacetylacetates, indium trifluoropentanedionates, andmixtures thereof.

Sources of gallium include gallium metal, trialkylgallium,trisdialkylamine gallium, gallium halides, gallium fluorides, galliumchlorides, gallium iodides, diethylgallium chlorides, gallium acetate,gallium 2,4-pentanedionate, gallium ethoxide, gallium2,2,6,6,-tetramethylheptanedionate, trisdimethylaminogallium, andmixtures thereof.

Some sources of gallium and indium are described in International PatentPublication No. WO2008057119.

Additional Sulfurization or Selenization

In various processes of this disclosure, a composition or material mayoptionally be subjected to a step of sulfurization or selenization.

Sulfurization with H₂S or selenization with H₂Se may be carried out byusing pure H₂₅ or H₂Se, respectively, or may be done by dilution inhydrogen or in nitrogen. Selenization can also be carried out with Sevapor, or other source of elemental selenium.

A sulfurization or selenization step can be done at any temperature fromabout 200° C. to about 600° C., or at temperatures below 200° C. One ormore steps of sulfurization and selenization may be performedconcurrently, or sequentially.

Examples of sulfurizing agents include hydrogen sulfide, hydrogensulfide diluted with hydrogen, elemental sulfur, sulfur powder, carbondisulfide, alkyl polysulfides, dimethyl sulfide, dimethyl disulfide, andmixtures thereof.

Examples of selenizing agents include hydrogen selenide, hydrogenselenide diluted with hydrogen, elemental selenium, selenium powder,carbon diselenide, alkyl polyselenides, dimethyl selenide, dimethyldiselenide, and mixtures thereof.

A sulfurization or selenization step can also be done with co-depositionof another metal such as copper, indium, or gallium.

Chemical Definitions

As used herein, the term (X,Y) when referring to compounds or atomsindicates that either X or Y, or a combination thereof may be found inthe formula. For example, (S,Se) indicates that atoms of either sulfuror selenium, or any combination thereof may be found. Further, usingthis notation the amount of each atom can be specified. For example,when appearing in the chemical formula of a molecule, the notation (0.75In,0.25 Ga) indicates that the atom specified by the symbols in theparentheses is indium in 75% of the compounds and gallium in theremaining 25% of the compounds, regardless of the identity any otheratoms in the compound. In the absence of a specified amount, the term(X,Y) refers to approximately equal amounts of X and Y.

The atoms S, Se, and Te of Group 16 are referred to as chalcogens.

As used herein, the letter “S” in CIGS refers to sulfur or selenium orboth. The letter “C” in CIGS refers to copper. The letter “I” in CIGSrefers to indium. The letter “G” in CIGS refers to gallium.

As used herein, the term CIGS includes the variations C(I,G)S and CIS,as well as CGS, unless described otherwise.

As used herein, the term CIGS includes the terms CIGSSe and CIGSe, andthese terms refer to compounds or materials containingcopper/indium/gallium/sulfur/selenium, which may contain sulfur orselenium or both.

As used herein, the term “chalcogenide” refers to a compound containingone or more chalcogen atoms bonded to one or more metal atoms.

The term “alkyl” as used herein refers to a hydrocarbyl radical of asaturated aliphatic group, which can be a branched or unbranched,substituted or unsubstituted aliphatic group containing from 1 to 22carbon atoms. This definition applies to the alkyl portion of othergroups such as, for example, cycloalkyl, alkoxy, alkanoyl, aralkyl, andother groups defined below. The term “cycloalkyl” as used herein refersto a saturated, substituted or unsubstituted cyclic alkyl ringcontaining from 3 to 12 carbon atoms. As used herein, the term“C(1-5)alkyl” includes C(1)alkyl, C(2)alkyl, C(3)alkyl, C(4)alkyl, andC(5)alkyl. Likewise, the term “C(3-22)alkyl” includes C(1)alkyl,C(2)alkyl, C(3)alkyl, C(4)alkyl, C(5)alkyl, C(6)alkyl, C(7)alkyl,C(8)alkyl, C(9)alkyl, C(10)alkyl, C(11)alkyl, C(12)alkyl, C(13)alkyl,C(14)alkyl, C(15)alkyl, C(16)alkyl, C(17)alkyl, C(18)alkyl, C(19)alkyl,C(20)alkyl, C(21)alkyl, and C(22)alkyl.

The term “alkenyl” as used herein refers to an unsaturated, branched orunbranched, substituted or unsubstituted alkyl or cycloalkyl having 2 to22 carbon atoms and at least one carbon-carbon double bond. The term“alkynyl” as used herein refers to an unsaturated, branched orunbranched, substituted or unsubstituted alkyl or cycloalkyl having 2 to22 carbon atoms and at least one carbon-carbon triple bond.

The term “alkoxy” as used herein refers to an alkyl, cycloalkyl,alkenyl, or alkynyl group covalently bonded to an oxygen atom. The term“alkanoyl” as used herein refers to —C(═O)-alkyl, which mayalternatively be referred to as “acyl.” The term “alkanoyloxy” as usedherein refers to —O—C(═O)-alkyl groups. The term “alkylamino” as usedherein refers to the group —NRR′, where R and R′ are each eitherhydrogen or alkyl, and at least one of R and R′ is alkyl. Alkylaminoincludes groups such as piperidino wherein R and R′ form a ring. Theterm “alkylaminoalkyl” refers to alkyl-NRR′.

The term “aryl” as used herein refers to any stable monocyclic,bicyclic, or polycyclic carbon ring system of from 4 to 12 atoms in eachring, wherein at least one ring is aromatic. Some examples of an arylinclude phenyl, naphthyl, tetrahydro-naphthyl, indanyl, and biphenyl.Where an aryl substituent is bicyclic and one ring is non-aromatic, itis understood that attachment is to the aromatic ring. An aryl may besubstituted or unsubstituted.

The term “heteroaryl” as used herein refers to any stable monocyclic,bicyclic, or polycyclic carbon ring system of from 4 to 12 atoms in eachring, wherein at least one ring is aromatic and contains from 1 to 4heteroatoms selected from oxygen, nitrogen and sulfur. Phosphorous andselenium may be a heteroatom. Some examples of a heteroaryl includeacridinyl, quinoxalinyl, pyrazolyl, indolyl, benzotriazolyl, furanyl,thienyl, benzothienyl, benzofuranyl, quinolinyl, isoquinolinyl,oxazolyl, isoxazolyl, pyrazinyl, pyridazinyl, pyridinyl, pyrimidinyl,pyrrolyl, and tetrahydroquinolinyl. A heteroaryl includes the N-oxidederivative of a nitrogen-containing heteroaryl.

The term “heterocycle” or “heterocyclyl” as used herein refers to anaromatic or nonaromatic ring system of from five to twenty-two atoms,wherein from 1 to 4 of the ring atoms are heteroatoms selected fromoxygen, nitrogen, and sulfur. Phosphorous and selenium may be aheteroatom. Thus, a heterocycle may be a heteroaryl or a dihydro ortetrathydro version thereof.

The term “aroyl” as used herein refers to an aryl radical derived froman aromatic carboxylic acid, such as a substituted benzoic acid. Theterm “aralkyl” as used herein refers to an aryl group bonded to an alkylgroup, for example, a benzyl group.

The term “carboxyl” as used herein represents a group of the formulaC(═O)OH or —C(═O)O⁻. The terms “carbonyl” and “acyl” as used hereinrefer to a group in which an oxygen atom is double-bonded to a carbonatom >C═O. The term “hydroxyl” as used herein refers to —OH or —O⁻. Theterm “nitrile” or “cyano” as used herein refers to CN. The term“halogen” or “halo” refers to fluoro (—F), chloro (Cl), bromo (—Br), andiodo (—I).

The term “substituted” as used herein refers to an atom having one ormore substitutions or substituents which can be the same or differentand may include a hydrogen substituent. Thus, the terms alkyl,cycloalkyl, alkenyl, alkynyl, alkoxy, alkanoyl, alkanoyloxy, alkylamino,alkylaminoalkyl, aryl, heteroaryl, heterocycle, aroyl, and aralkyl asused herein refer to groups which include substituted variations.Substituted variations include linear, branched, and cyclic variations,and groups having a substituent or substituents replacing one or morehydrogens attached to any carbon atom of the group. Substituents thatmay be attached to a carbon atom of the group include alkyl, cycloalkyl,alkenyl, alkynyl, alkoxy, alkanoyl, alkanoyloxy, alkylamino,alkylaminoalkyl, aryl, heteroaryl, heterocycle, aroyl, aralkyl, acyl,hydroxyl, cyano, halo, haloalkyl, amino, aminoacyl, alkylaminoacyl,acyloxy, aryloxy, aryloxyalkyl, mercapto, nitro, carbamyl, carbamoyl,and heterocycle. For example, the term ethyl includes without limitation—CH₂CH₃, —CHFCH₃, —CF₂CH₃, —CHFCH₂F, —CHFCHF₂, —CHFCF₃, —CF₂CH₂F,—CF₂CHF₂, —CF₂CF₃, and other variations as described above. In general,a substituent may itself be further substituted with any atom or groupof atoms.

Some examples of a substituent for a substituted alkyl include halogen,hydroxyl, carbonyl, carboxyl, ester, aldehyde, carboxylate, formyl,ketone, thiocarbonyl, thioester, thioacetate, thioformate,selenocarbonyl, selenoester, selenoacetate, selenoformate, alkoxyl,phosphoryl, phosphonate, phosphinate, amino, amido, amidine, imino,cyano, nitro, azido, carbamato, sulfhydryl, alkylthio, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, silyl, heterocyclyl, aryl,aralkyl, aromatic, and heteroaryl.

It will be understood that “substitution” or “substituted with” refersto such substitution that is in accordance with permitted valence of thesubstituted atom and the substituent. As used herein, the term“substituted” includes all permissible substituents.

In general, a compound may contain one or more chiral centers. Compoundscontaining one or more chiral centers may include those described as an“isomer,” a “stereoisomer,” a “diastereomer,” an “enantiomer,” an“optical isomer,” or as a “racemic mixture.” Conventions forstereochemical nomenclature, for example the stereoisomer naming rulesof Cahn, Ingold and Prelog, as well as methods for the determination ofstereochemistry and the separation of stereoisomers are known in theart. See, for example, Michael B. Smith and Jerry March, March'sAdvanced Organic Chemistry, 5th edition, 2001. The compounds andstructures of this disclosure are meant to encompass all possibleisomers, stereoisomers, diastereomers, enantiomers, and/or opticalisomers that would be understood to exist for the specified compound orstructure, including any mixture, racemic or otherwise, thereof.

This invention encompasses any and all tautomeric, solvated orunsolvated, hydrated or unhydrated forms, as well as any atom isotopeforms of the compounds and compositions disclosed herein.

This invention encompasses any and all crystalline polymorphs ordifferent crystalline forms of the compounds and compositions disclosedherein.

Additional Embodiments

All publications, references, patents, patent publications and patentapplications cited herein are each hereby specifically incorporated byreference in their entirety for all purposes.

While this invention has been described in relation to certainembodiments, aspects, or variations, and many details have been setforth for purposes of illustration, it will be apparent to those skilledin the art that this invention includes additional embodiments, aspects,or variations, and that some of the details described herein may bevaried considerably without departing from this invention. Thisinvention includes such additional embodiments, aspects, and variations,and any modifications and equivalents thereof. In particular, thisinvention includes any combination of the features, terms, or elementsof the various illustrative components and examples.

The use herein of the terms “a,” “an,” “the” and similar terms indescribing the invention, and in the claims, are to be construed toinclude both the singular and the plural.

The terms “comprising,” “having,” “include,” “including” and“containing” are to be construed as open-ended terms which mean, forexample, “including, but not limited to.” Thus, terms such as“comprising,” “having,” “include,” “including” and “containing” are tobe construed as being inclusive, not exclusive.

Recitation of a range of values herein refers individually to each andany separate value falling within the range as if it were individuallyrecited herein, whether or not some of the values within the range areexpressly recited. For example, the range “4 to 12” includes withoutlimitation any whole, integer, fractional, or rational value greaterthan or equal to 4 and less than or equal to 12, as would be understoodby those skilled in the art. Specific values employed herein will beunderstood as exemplary and not to limit the scope of the invention.

Recitation of a range of a number of atoms herein refers individually toeach and any separate value falling within the range as if it wereindividually recited herein, whether or not some of the values withinthe range are expressly recited. For example, the term “C1-8” includeswithout limitation the species C1, C2, C3, C4, C5, C6, C7, and C8.

Definitions of technical terms provided herein should be construed toinclude without recitation those meanings associated with these termsknown to those skilled in the art, and are not intended to limit thescope of the invention. Definitions of technical terms provided hereinshall be construed to dominate over alternative definitions in the artor definitions which become incorporated herein by reference to theextent that the alternative definitions conflict with the definitionprovided herein.

The examples given herein, and the exemplary language used herein aresolely for the purpose of illustration, and are not intended to limitthe scope of the invention. All examples and lists of examples areunderstood to be non-limiting.

When a list of examples is given, such as a list of compounds, moleculesor compositions suitable for this invention, it will be apparent tothose skilled in the art that mixtures of the listed compounds,molecules or compositions may also be suitable.

EXAMPLES

Thermogravimetric analysis (TGA) was performed using a Q50Thermogravimetric Analyzer (TA Instruments, New Castle, Del.). NMR datawere recorded using a Varian 400 MHz spectrometer.

Example 1 Polymeric Precursor Compounds

A polymeric precursor represented by the formula {Cu(Se^(sec)Bu)₄In} wassynthesized using the following procedure.

To a stirred solution of In(Se^(sec)Bu)₃ (2.60 g, 5 mmol) in benzene (10mL) under inert atmosphere was added solid CuSe^(sec)Bu (1.0 g, 5 mmol).The mixture was stirred at 25° C. for 12 h to produce a pale yellowsolution. The solvent was removed from the reaction mixture underreduced pressure leaving a sticky yellow oil. The oil was dissolved inpentane and filtered. Solvent removal from the filtrate under reducedpressure yielded 3.1 g (86%).

NMR: (1H; C6D6) 0.99 (br, 12H), 1.70 (br d, 12H), 1.81 (m, 4H), 2.02 (brm, 4H), 3.67 (br, 4H).

In FIG. 8 is shown the TGA for this MPP polymeric precursor. The TGAshowed a transition beginning at about 190° C., having a midpoint atabout 210° C., and ending at about 230° C. The yield for the transitionwas 46.6% (w/w), as compared to a theoretical yield for the formulaCuInSe₂ of 46.5% (w/w). Thus, the TGA showed that this polymericprecursor can be used to prepare CuInSe₂ layers and materials, and canbe used as a component to prepare other semiconductor layers, crystals,and materials.

Example 2

A polymeric precursor represented by the formula {Cu(Se^(sec)Bu)₄Ga} wassynthesized using the following procedure.

To a stirred solution of Ga(Se^(sec)Bu)₃ (1.20 g, 2.5 mmol) in benzene(10 mL) under inert atmosphere was added solid CuSe^(sec)Bu (0.51 g, 2.5mmol). The mixture was stirred at 25° C. for 2 h to produce a paleyellow solution. The solvent was removed from the reaction mixture underreduced pressure leaving a sticky yellow oil. The oil was dissolved inpentane and filtered. Solvent removal from the filtrate under reducedpressure yielded 1.50 g (89%).

NMR: (1H; CDCl₃) 0.98 (t, 12H), 1.58 (br, 12H), 1.74 (br, 4H), 1.96 (br,4H), 3.44 (br, 4H).

In FIG. 9 is shown the TGA for this MPP polymeric precursor. The TGAshowed a transition beginning at about 100° C. and ending at about 240°C. The yield for the transition was 44% (w/w), as compared to atheoretical yield for the formula CuGaSe₂ of 43% (w/w). Thus, the TGAshowed that this polymeric precursor can be used to prepare

CuGaSe₂ layers and materials, and can be used as a component to prepareother semiconductor layers, crystals, and materials.

Example 3

A polymeric precursor represented by the formula {Cu(S^(t)Bu)₄In} wassynthesized using the following procedure.

A 100-mL Schlenk tube was charged with In(S^(t)Bu)₃ (0.55 g, 1.4 mmol)and CuS^(t)Bu (0.21 g, 1.4 mmol). 10 mL of dry benzene was added. Thereaction mixture was heated at 75° C. overnight. A colorless solidformed. The solution was filtered and the solid was washed with benzeneat room temperature. The solid was dried under vacuum and collected (0.4g, yield, 53%).

Elemental analysis: C, 36.2, H, 6.7, Cu, 13.0, In, 23.9, S, 18.0. NMR:(1H) 1.66 (br s 36H); (13C) 23.15 (s); 26.64 (s); 37.68 (s); 47.44 (s).

The TGA for this polymeric precursor showed a transition having amidpoint at 218° C., ending at 225° C. The yield for the transition was46% (w/w), as compared to a theoretical yield for the formula CuInS₂ of45% (w/w). Thus, the TGA showed that this polymeric precursor can beused to prepare CuInS₂ layers and materials, and can be used as acomponent to prepare other semiconductor layers, crystals, andmaterials.

Example 4

A polymeric precursor represented by the formula{Cu(Se^(t)Bu)(Se^(n)Bu)In(Se^(n)Bu)₂} was synthesized using thefollowing procedure.

In an inert atmosphere glovebox, a Schlenk tube was charged with 2.0 g(3.8 mmol) of 1n(Se^(n)Bu)₃ and 0.76 g (3.8 mmol) of CuSe^(t)Bu. Benzene(10 mL) was then added to the Schlenk tube. The Schlenk tube was thentransferred to a Schlenk line and the reaction mixture was heated for 12h at 70° C. The solvent was removed under reduced pressure and the crudeproduct was extracted with pentane, resulting in an orange pentanesolution. The solution was concentrated and stored at −60° C. for 12 hresulting in formation of a solid coating the flask walls. The filtratewas decanted and the solid was dried under reduced pressure leading forformation of a low melting solid (foam-like). Upon mild heating with aheat gun, an orange oil was formed and isolated (1.4 g, 51%). Thesolvent from the filtrate was removed under vacuum leaving an additionalquantity of orange oil that was isolated (0.28 g, 10%).

In FIG. 10 is shown the TGA for this MPP polymeric precursor. The TGAshowed a transition beginning at about 140° C., having a midpoint atabout 195° C., and ending at about 245° C. The yield for the transitionwas 48.8% (w/w), as compared to a theoretical yield for the formulaCuInSe₂ of 46.6% (w/w). Thus, the TGA showed that this polymericprecursor can be used to prepare CuInSe₂ layers and materials, and canbe used as a component to prepare other semiconductor layers, crystals,and materials.

Elemental analysis: C, 25.21, H, 4.83, Cu, 12.28, In, 16.25, S, 44.08.NMR: (1H) 0.91 (t, J=7.2Hz, 9H); 1.41 (m, 6H); 1.69 (s, 9H); 1.75 (m,6H); 2.84 (br s, 6H).

Example 5

A polymeric precursor represented by the formula{Cu_(0.95)(Se^(t)Bu)_(3.95)Ga} was synthesized using the followingprocedure.

In an inert atmosphere glovebox, toluene (ca. 15 mL) was added to amixture of CuSe^(t)Bu (0.40 g, 2.0 mmol) and Ga(Se^(t)Bu)₃ (1.0 g, 2.1mmol) in a Schlenk tube. The Schlenk tube was then transferred to aSchlenk line and the reaction mixture was heated at 105° C. for 12 h,resulting in formation of a pale yellow precipitate. The reactionmixture was filtered hot and the solid residue was washed with hottoluene (3×15 mL, ca. 100° C.). Subsequent drying under reduced pressureafforded 1.0 g of pale yellow solid (74%).

In FIG. 11 is shown the TGA for this MPP polymeric precursor. The TGAshowed a transition beginning at about 120° C., having a midpoint atabout 150° C., and ending at about 175° C. The yield for the transitionwas 46.9% (w/w), as compared to a theoretical yield for the formulaCu_(0.95)GaSe₂ of 43.1% (w/w). Thus, the TGA showed that this polymericprecursor can be used to prepare CuGaSe₂ layers and materials, and canbe used as a component to prepare other semiconductor layers, crystals,and materials.

Example 6

A polymeric precursor represented by the formula{Cu(S^(t)Bu)(SEt)Ga(SEt)₂} was synthesized using the followingprocedure.

In an inert atmosphere glovebox, benzene (ca. 15 mL) was added to amixture of CuS^(t)Bu (0.60 g, 3.95 mmol) and Ga(SEt)₃ (1.0 g, 3.95 mmol)in a Schlenk tube. The Schlenk tube was transferred to a Schlenk lineand the reaction mixture was heated at 100° C. for 12 h. The solvent wasthen removed under reduced pressure leaving a pale yellow oil (1.3 g,81%).

NMR: (1H, C₆D₆) 1.2-1.9 (multiplets, 18H); 3.0 (m, 6H).

The TGA for this polymeric precursor showed a transition beginning at100° C., with a midpoint at 150° C., and ending at 260° C.

Example 7

A polymeric precursor represented by the formula{Cu(S^(t)Bu)₂Ga(S^(t)Bu)₂} was synthesized using the followingprocedure.

In an inert atmosphere glovebox, benzene (ca. 10 mL) was added to amixture of CuS^(t)Bu (0.23 g, 1.5 mmol) and Ga(S^(t)Bu)₃ (0.50 g, 1.5mmol) in a Schlenk tube. The Schlenk tube was transferred to a Schlenkline and the reaction mixture was heated at 90-95° C. for 12 h,resulting in formation of a white precipitate. The reaction mixture wasfiltered hot and the white solid was washed with hot benzene (3×10 mL,80° C.). After drying the solid under reduced pressure, 0.36 g ofcolorless solid was isolated (55%).

Elemental analysis: C, 38.90, H, 7.23, Cu, 12.3, Ga, 12.9, S, 24.94.

The TGA for this polymeric precursor showed a transition ending at 210°C. The yield for the transition was 40.95% (w/w), as compared to atheoretical yield for the formula CuGaS₂ of 40.3% (w/w). Thus, the TGAshowed that this polymeric precursor can be used to prepare CuGaS₂layers and materials, and can be used as a component to prepare othersemiconductor layers, crystals, and materials.

Example 8

A polymeric precursor represented by the formula{Cu(Se^(t)Bu)(Se^(n)Bu)Ga(Se^(n)Bu)₂} was synthesized using thefollowing procedure.

In an inert atmosphere glovebox, a Schlenk tube was charged withGa(Se^(n)Bu)₃(0.98 g, 2.0 mmol) and CuSe^(t)Bu (0.40 g, 2.0 mmol).Benzene (10 mL) was then added to the Schlenk tube. The Schlenk tube wasthen transferred to a Schlenk line and the reaction mixture was heatedat 75° C. for 12 h. The solvent was removed under reduced pressure andthe product was extracted with pentane. Filtration and subsequentsolvent removal under reduced pressure afforded a yellow oil (1.1 g,81%).

NMR: (1H) 0.92 (br s, 9H, CH3); 1.49 (br s, 6H, CH2); 1.87 (s, 9H, tBu);1.96 (br s, 6H, CH2); 3.15 (br s, 6H, CH2).

The TGA for this polymeric precursor showed a transition beginning atabout 100° C., and ending at about 250° C. The yield for the transitionwas 45% (w/w), as compared to a theoretical yield for the formulaCuGaSe₂ of 43% (w/w). Thus, the TGA showed that this polymeric precursorcan be used to prepare CuGaSe₂ layers and materials, and can be used asa component to prepare other semiconductor layers, crystals, andmaterials.

Example 9

A polymeric precursor represented by the formula {Cu(S^(t)Bu)₂(0.75In,0.25 Ga)(S^(t)Bu)₂} was synthesized using the following procedure.

In an inert atmosphere glovebox, a Schlenk tube was charged withIn(S^(t)Bu)₃ (0.29 g, 0.75 mmol), Ga(S^(t)Bu)₃ (0.084 g, 0.25 mmol), andCuS^(t)Bu (0.15 g, 1.0 mmol). Toluene was then added to the Schlenk tube(10 mL). The Schlenk tube was transferred to a Schlenk line and heatedin an oil bath at 80° C. for 12 h, resulting in formation of a whiteprecipitate. The reaction mixture was filtered, the remaining solid waswashed with benzene, dried under reduced pressure, and collected (0.35g, 67%).

Elemental analysis: C, 36.67, H, 6.82, Cu, 11.9, In, 17.8, Ga, 2.93, S,20.26.

In FIG. 12 is shown the TGA for this MPP polymeric precursor. The TGAshowed a transition beginning at about 160° C., having a midpoint atabout 227° C., and ending at about 235° C. The yield for the transitionwas 45.3% (w/w), as compared to a theoretical yield for the formulaCu(0.75 In,0.25 Ga)S₂ of 44.1% (w/w). Thus, the TGA showed that thispolymeric precursor can be used to prepare CIGS layers and materials,and can be used as a component to prepare other semiconductor layers,crystals, and materials.

Example 10

A polymeric precursor represented by the formula {Cu(S^(t)Bu)₂(0.9In,0.1 Ga)(S^(t)Bu)₂} was synthesized using the following procedure.

In an inert atmosphere glovebox, a Schlenk tube was charged withIn(S^(t)Bu)₃ (0.34 g, 0.9 mmol), Ga(S^(t)Bu)₃ (0.034 g, 0.1 mmol), andCuS^(t)Bu (0.15 g, 1.0 mmol). Toluene was then added to the Schlenk tube(10 mL). The Schlenk tube was transferred to a Schlenk line and heatedin an oil bath at 80° C. for 12 h, resulting in formation of a whiteprecipitate. The reaction mixture was filtered, the remaining solid waswashed with benzene, dried under reduced pressure, and collected (0.35g, 66% yield).

Elemental analysis: C, 35.96, H, 6.31, Cu, 12.6, In, 20.0, Ga, 1.12, S,22.12.

In FIG. 13 is shown the TGA for this MPP polymeric precursor. The TGAshowed a transition having a midpoint at about 220° C., and ending atabout 230° C. The yield for the transition was 46.2% (w/w), as comparedto a theoretical yield for the formula Cu(0.9 In,0.1 Ga)S₂ of 44.8%(w/w). Thus, the TGA showed that this polymeric precursor can be used toprepare CIGS layers and materials, and can be used as a component toprepare other semiconductor layers, crystals, and materials.

Example 11

A polymeric precursor represented by the formula{Cu(Se^(t)Bu)(Se^(n)Bu)(0.3 In,0.7 Ga)(Se^(n)Bu)₂} was synthesized usingthe following procedure.

In an inert atmosphere glovebox, a Schlenk tube was charged withIn(Se^(n)Bu)₃(0.31 g, 0.6 mmol), Ga(Se^(n)Bu)₃ (0.67 g, 1.4 mmol), andCuSe^(t)Bu (0.40 g, 2.0 mmol). Toluene (10 mL) was added to the Schlenktube. The Schlenk tube was transferred to a Schlenk line and thereaction mixture was heated at 80° C. for 12 h. The solvent was removedunder vacuum and the product was extracted with pentane. Filtration andsolvent removal under reduced pressure afforded 1.2 g (81%) of anorange-red oil.

Elemental analysis: C, 26.86, H, 4.74, Cu, 10.2, In, 4.57, Ga, 7.63.NMR: (1H) 0.94 (br s, 9H, CH3); 1.51 (br s, 6H, CH2); 1.89 (s, 9H, tBu);1.96 (br s, 6H, CH2); 3.12 (br s, 6H, CH2); (13C) 13.96 (s); 23.79 (s);36.37 (br s); 37.38 (br s).

The TGA for this polymeric precursor showed a transition beginning atabout 115° C., having a midpoint at about 200° C., and ending at about265° C. The yield for the transition was 48.5% (w/w), as compared to atheoretical yield for the formula Cu(0.3 In,0.7 Ga)Se₂ of 44% (w/w).Thus, the TGA showed that this polymeric precursor can be used toprepare CIGS layers and materials, and can be used as a component toprepare other semiconductor layers, crystals, and materials.

Example 12

A polymeric precursor represented by the formula{Cu(Se^(t)Bu)(Se^(n)Bu)(0.5 In,0.5 Ga)(Se^(n)Bu)₂} was synthesized usingthe following procedure.

In an inert atmosphere glovebox, a Schlenk tube was charged withIn(Se^(n)Bu)₃(0.52 g, 1.0 mmol), Ga(Se^(n)Bu)₃ (0.49 g, 1.0 mmol), andCuSe^(t)Bu (0.40 g, 2.0 mmol). Toluene (10 mL) was added to the Schlenktube. The Schlenk tube was transferred to a Schlenk line and thereaction mixture was heated at 80° C. for 12 h. The solvent was removedunder reduced pressure and the product was extracted with pentane.Filtration and solvent removal under reduced pressure afforded 1.26 g(86%) of an orange-red oil.

Elemental analysis: C, 22.07, H, 4.05, Cu, 10.2, In, 7.95, Ga, 5.39.NMR: (1H) 0.93 (br s, 9H, CH3); 1.5 (br s, 6H, CH2); 1.88 (s, 9H, tBu);1.96 (br s, 6H, CH2); 3.13 (br s, 6H, CH2); (13C) 13.92 (s); 23.74 (s);36.11 (br s); 37.31 (br s).

The TGA for this polymeric precursor showed a transition beginning atabout 90° C., and ending at about 233° C. The yield for the transitionwas 46.9% (w/w), as compared to a theoretical yield for the formulaCu(0.5 In,0.5 Ga)Se₂ of 44.8% (w/w). Thus, the TGA showed that thispolymeric precursor can be used to prepare CIGS layers and materials,and can be used as a component to prepare other semiconductor layers,crystals, and materials.

Example 13

A polymeric precursor represented by the formula{Cu(Se^(t)Bu)(Se^(n)Bu)(0.7 In,0.3 Ga)(Se^(n)Bu)₂} was synthesized usingthe following procedure.

In an inert atmosphere glovebox, a Schlenk tube was charged withIn(Se^(n)Bu)₃(0.60 g, 1.1 mmol), Ga(Se^(n)Bu)₃ (0.23 g, 0.49 mmol), andCuSe^(t)Bu (0.32 g, 1.6 mmol). Toluene (10 mL) was then added to theSchlenk tube. The Schlenk tube was then transferred to a Schlenk lineand the reaction mixture was heated at 80° C. for 12 h. The solvent wasremoved under reduced pressure and the product was extracted withpentane. Filtration and solvent removal under reduced pressure afforded0.98 g (83%) of an orange-red oil.

Elemental analysis: C, 25.23, H, 4.56, Cu, 10.4, In, 11.3, Ga, 3.19.NMR: (1H) 0.90 (br s, 9H, CH3); 1.45 (br s, 6H, CH2); 1.83 (s, 9H, tBu);1.93 (br s, 6H, CH2); 3.12 (br s, 6H, CH2); (13C) 13.88 (s); 23.60 (s);36.89 (br s); 37.77 (br s).

In FIG. 14 is shown the TGA for this MPP polymeric precursor. The TGAshowed a transition beginning at about 115° C., and ending at about 245°C. The yield for the transition was 49.3% (w/w), as compared to atheoretical yield for the formula Cu(0.7 In,0.3 Ga)Se₂ of 45.5% (w/w).Thus, the TGA showed that this polymeric precursor can be used toprepare CIGS layers and materials, and can be used as a component toprepare other semiconductor layers, crystals, and materials.

Example 14

A polymeric precursor represented by the formula{Cu(Se^(t)Bu)(Se^(n)Bu)(0.75 In,0.25 Ga)(Se^(n)Bu)₂} was synthesizedusing the following procedure.

In an inert atmosphere glovebox, a Schlenk tube was charged withIn(Se^(t)Bu)₃(0.79 g, 1.5 mmol), Ga(Se^(t)Bu)₃ (0.24 g, 0.5 mmol), andCuSe^(t)Bu (0.4 g, 2.0 mmol). Toluene (10 mL) was then added to theSchlenk tube. The Schlenk tube was transferred to a Schlenk line and thereaction mixture was heated at 80° C. for 12 h. The solvent was removedunder reduced pressure and the product was extracted with pentane.Filtration and solvent removal under reduced pressure afforded 1.24 g(85%) of an orange-red oil.

Elemental analysis: C, 25.26, H, 4.68, Cu, 9.66, In, 11.5, Ga, 2.66.NMR: (1H) 0.92 (br s, 9H, CH3); 1.48 (br s, 6H, CH2); 1.87 (br s, 9H,tBu); 1.95 (br s, 6H, CH2); 3.13 (br s, 6H, CH2); (13C) 13.89 (s); 23.59(br s); 36.89 (br s); 37.88 (br s).

In FIG. 15 is shown the TGA for this MPP polymeric precursor. The TGAshowed a transition beginning at about 100° C., having a midpoint atabout 200° C., and ending at about 240° C. The yield for the transitionwas 47.3% (w/w), as compared to a theoretical yield for the formulaCu(0.75 In,0.25 Ga)Se₂ of 45.7% (w/w). Thus, the TGA showed that thispolymeric precursor can be used to prepare CIGS layers and materials,and can be used as a component to prepare other semiconductor layers,crystals, and materials.

Example 15

A polymeric precursor represented by the formula{Cu(Se^(t)Bu)(Se^(n)Bu)(0.9 In,0.1 Ga)(Se^(n)Bu)₂} was synthesized usingthe following procedure.

In an inert atmosphere glovebox, a Schlenk tube was charged withIn(Se^(t)Bu)₃(0.94 g, 1.8 mmol), Ga(Se^(t)Bu)₃ (0.096 g, 0.2 mmol), andCuSe^(t)Bu (0.4 g, 2.0 mmol). Toluene (10 mL) was then added to theSchlenk tube. The Schlenk tube was transferred to a Schlenk line and thereaction mixture was heated at 80° C. for 12 h. The solvent was removedunder reduced pressure and the product was extracted with pentane.Filtration and solvent removal under reduced pressure afforded 1.22 g(85%) of an orange-red oil.

Elemental analysis: C, 25.02, H, 4.62, Cu, 10.5, In, 14.6, Ga, 1.06.NMR: (1H) 0.92 (br s, 9H, CH3); 1.45 (br s, 6H, CH2); 1.84 (s, 9H, tBu);1.95 (br s, 6H, CH2); 3.13 (br s, 6H, CH2); (13C) 13.89 (s); 23.63 (brs); 36.91 (br s); 37.83 (br s).

The TGA for this polymeric precursor showed a transition beginning atabout 115° C., having a midpoint at about 200° C., and ending at about245° C. The yield for the transition was 49.3% (w/w), as compared to atheoretical yield for the formula Cu(0.9 In,0.1 Ga)Se₂ of 46.2% (w/w).Thus, the TGA showed that this polymeric precursor can be used toprepare CIGS layers and materials, and can be used as a component toprepare other semiconductor layers, crystals, and materials.

Example 16

A polymeric precursor represented by the formulaCu_(0.85)(Se^(t)BU)_(0.85)(Se^(n)Bu)(In_(0.7),Ga_(0.3))(Se^(n)Bu)₂} wassynthesized using the following procedure.

In an inert atmosphere glovebox, a Schlenk tube was charged withIn(Se^(n)Bu)₃(0.73 g, 1.4 mmol), Ga(Se^(n)Bu)₃ (0.29 g, 0.6 mmol), andCuSe^(t)Bu (0.34 g, 1.7 mmol). Toluene (10 mL) was added. The Schlenktube was transferred to a Schlenk line and the reaction mixture washeated at 80° C. for 12 h. The solvent was removed under reducedpressure and the product was extracted with pentane. Filtration andsolvent removal under reduced pressure afforded 1.0 g (71%) of anorange-red oil.

Elemental analysis: C, 25.47, H, 4.65, Cu, 8.09, In, 10.5, Ga, 2.97.NMR: (1H) 0.94 (br s, 9H, CH3); 1.50 (br s, 6H, CH2); 1.87 (s, 9H, tBu);1.97 (br s, 6H, CH2); 3.13 (br s, 6H, CH2).

In FIG. 16 is shown the TGA for this MPP polymeric precursor. The TGAshowed a transition beginning at about 110° C., having a midpoint atabout 195° C., and ending at about 230° C. The yield for the transitionwas 46.4% (w/w), as compared to a theoretical yield for the formula(0.85 Cu)(0.7 In,0.3 Ga)Se₂ of 46.1% (w/w). Thus, the TGA showed thatthis polymeric precursor can be used to prepare Cu(In,Ga)Se₂ layers andmaterials, and can be used as a component to prepare other semiconductorlayers, crystals, and materials.

Example 17

A range of polymeric molecular precursors shown in Table 2 weresynthesized in an inert atmosphere according to the following generalprocedure. A Schlenk tube was charged in an inert atmosphere gloveboxwith M^(B)(ER)₃ and Cu(ER). A solvent, typically toluene or benzene, wasthen added. The Schlenk tube was transferred to a Schlenk line and thereaction mixture was stirred at 25° C. for 1 h. In some cases, thereaction mixture was stirred at about 80° C. for up to 12 h. The solventwas removed under reduced pressure and the product was extracted withpentane. The pentane extract was filtered and the solvent was removedunder reduced pressure to afford a yellow to yellow-orange product. Theproducts ranged from being an oil, to being a semi-solid, to being asolid. Yields of 90% or greater were typical.

TABLE 2 Examples of polymeric molecular precursors Polymeric TGA TargetMolecular Precursor Material Target Yield % %[Cu_(1.0)In_(1.0)(Se^(s)Bu)₄]_(n) Cu_(1.0)In_(1.0)Se₂ 46.6 46.5[Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(s)Bu)₄]_(n) Cu_(1.0)In_(0.9)Ga_(0.1)Se₂46.3 46.2 [Cu_(1.0)In_(0.8)Ga_(0.2)(Se^(s)Bu)₄]_(n)Cu_(1.0)In_(0.8)Ga_(0.2)Se₂ 45.2 45.9[Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)₄]_(n) Cu_(1.0)In_(0.7)Ga_(0.3)Se₂46.0 45.5 [Cu_(1.0)In_(0.6)Ga_(0.4)(Se^(s)Bu)₄]_(n)Cu_(1.0)In_(0.6)Ga_(0.4)Se₂ 49.0 45.2[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(s)Bu)₄]_(n) Cu_(1.0)In_(0.5)Ga_(0.5)Se₂45.8 44.8 [Cu_(1.0)In_(0.3)Ga_(0.7)(Se^(s)Bu)₄]_(n)Cu_(1.0)In_(0.3)Ga_(0.7)Se₂ 48.9 44.1[Cu_(1.0)In_(0.1)Ga_(0.9)(Se^(s)Bu)₄]_(n) Cu_(1.0)In_(0.1)Ga_(0.9)Se₂49.0 43.4 [Cu_(1.0)Ga_(1.0)(Se^(s)Bu)₄]_(n) Cu_(1.0)Ga_(1.0)Se₂ 44.043.0 [Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.85)]_(n)Cu_(0.85)In_(0.7)Ga_(0.3)Se₂ 46.7 46.1[Cu_(0.90)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.90)]_(n)Cu_(0.90)In_(0.7)Ga_(0.3)Se₂ 47.8 45.9[Cu_(0.95)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.95)]_(n)Cu_(0.95)In_(0.7)Ga_(0.3)Se₂ 47.4 45.7[Cu_(1.0)In_(1.0)(Se^(n)Hex)₄]_(n) Cu_(1.0)In_(1.0)Se₂ 38.3 40.3[Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(n)Hex)₄]_(n) Cu_(1.0)In_(0.9)Ga_(0.1)Se₂42.8 40.0 [Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(n)Hex)₄]_(n)Cu_(1.0)In_(0.7)Ga_(0.3)Se₂ 39.5 39.3[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(n)Hex)₄]_(n) Cu_(1.0)In_(0.5)Ga_(0.5)Se₂37.9 38.6 [Cu_(1.0)In_(0.3)Ga_(0.7)(Se^(n)Hex)₄]_(n)Cu_(1.0)In_(0.3)Ga_(0.7)Se₂ 38.0 37.9 [Cu_(1.0)Ga_(1.0)(Se^(n)Hex)₄]_(n)Cu_(1.0)Ga_(1.0)Se₂ 38.3 36.9[Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.85)]_(n)Cu_(0.85)In_(0.7)Ga_(0.3)Se₂ 40.7 39.8[Cu_(0.90)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.90)]_(n)Cu_(0.90)In_(0.7)Ga_(0.3)Se₂ 40.3 39.6 [Cu_(1.0)In_(1.0)(Se^(n)Bu)₄]_(n)Cu_(1.0)In_(1.0)Se₂ 47.2 46.5 [Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(n)Bu)₄]_(n)Cu_(1.0)In_(0.7)Ga_(0.3)Se₂ 43.8 45.5 [Cu_(1.0)Ga_(1.0)(Se^(n)Bu)₄]_(n)Cu_(1.0)Ga_(1.0)Se₂ 43.8 43.0[Cu_(1.0)In_(1.0)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) Cu_(1.0)In_(1.0)Se₂ 48.846.6 [Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.9)Ga_(0.1)Se₂ 49.3 46.2[Cu_(1.0)In_(0.75)Ga_(0.25)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.75)Ga_(0.25)Se₂ 47.3 45.7[Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.7)Ga_(0.3)Se₂ 49.3 45.5[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.5)Ga_(0.5)Se₂ 46.9 44.8[Cu_(1.0)In_(0.3)Ga_(0.7)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.3)Ga_(0.7)Se₂ 48.5 44.1[Cu_(1.0)In_(0.1)Ga_(0.9)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.1)Ga_(0.9)Se₂ 44.2 43.4[Cu_(1.0)Ga_(1.0)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) Cu_(1.0)Ga_(1.0)Se₂ 45.043.0 [Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.85)]_(n)Cu_(0.85)In_(0.7)Ga_(0.3)Se₂ 46.4 46.1[Cu_(0.90)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.90)]_(n)Cu_(0.90)In_(0.7)Ga_(0.3)Se₂ 46.5 45.9[Cu_(1.0)Ga_(1.0)(Se^(t)Bu)_(4.0)]_(n) Cu_(1.0)Ga_(1.0)Se₂ 46.7 43.0[Cu_(0.95)Ga_(1.0)(Se^(t)Bu)_(3.95)]_(n) Cu_(1.0)Ga_(1.0)Se₂ 46.9 43.1[Cu_(1.0)In_(1.0)(Se^(s)Bu)₃(Se^(t)Bu)]_(n) Cu_(1.0)In_(1.0)Se₂ 45.446.5 [Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.7)Ga_(0.3)Se₂ 42.8 45.5[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(s)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.5)Ga_(0.5)Se₂ 41.3 44.8[Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(s)Bu)₃(Se^(t)Bu)_(0.85)]_(n)Cu_(0.85)In_(0.7)Ga_(0.3)Se₂ 44.2 46.1[Cu_(1.0)In_(1.0)(Se(2-EtHex))₄]_(n) Cu_(1.0)In_(1.0)Se₂ 35.9 35.5[Cu_(1.0)In_(1.0)(SePh)₃(Se^(n)Hex)]_(n) Cu_(1.0)In_(1.0)Se₂ 43.4 41.5[Cu_(1.0)In_(0.9)Ga_(0.1)(S^(t)Bu)₄]_(n) Cu_(1.0)In_(0.9)Ga_(0.1)S₂ 46.244.8 [Cu_(1.0)In_(0.75)Ga_(0.25)(S^(t)Bu)₄]_(n)Cu_(1.0)In_(0.75)Ga_(0.25)S₂ 45.3 44.1 [Cu_(1.0)Ga_(1.0)(S^(t)Bu)₄]_(n)Cu_(1.0)Ga_(1.0)S₂ 41.0 40.3 [Cu_(1.0)In_(1.0)(S^(t)Bu)₄]_(n)Cu_(1.0)In_(1.0)S₂ 46.0 45.0 [Cu_(1.0)Ga_(1.0)(SEt)₃(S^(t)Bu)]_(n)Cu_(1.0)Ga_(1.0)S₂ 49.8 48.6[Cu_(1.3)In_(1.0)(Se^(n)Bu)₃(Se^(t)Bu)_(1.3)]_(n)Cu_(1.3)In_(1.0)Se_(2.15) 47.5 46.9[Cu_(1.1)In_(1.0)(Se^(n)Bu)₃(Se^(t)Bu)_(1.1)]_(n)Cu_(1.1)In_(1.0)Se_(2.05) 46.5 46.7[Cu_(1.1)In_(0.65)Ga_(0.25)(Se^(n)Bu)₃(Se^(t)Bu)_(1.1)]_(n)Cu_(1.1)In_(0.65)Ga_(0.25)Se_(2.05) 46.1 45.5

Example 18 Preparation of Monomer Compounds

A monomer compound represented by the formula Ga(Se^(n)Bu)₃ wassynthesized using the following procedure.

To a 500-mL round bottom Schlenk flask in an inert atmosphere glove boxwas added NaSe^(n)Bu (28 g, 176 mmol) and THF (200 mL). The flask wasthen transferred to a Schlenk line and a solution of GaCl₃ (10.3 g, 59mmol) in 20 mL of benzene was then added. The reaction mixture wasstirred for 12 h and the volatiles were removed under reduced pressure.The residue was extracted with toluene and filtered. The volatiles fromthe filtrate were then removed under reduced pressure leaving acolorless oil (23 g, 48 mmol, 83% yield).

NMR: (1H; C6D6): 0.85 (t, J_(HH)=7.2Hz, 9H, CH3); 1.40 (m, 6H, —CH₂—);1.77 (m, 6H, —CH₂—); 3.03 (br s, 6H, SeCH₂—).

Example 19

A monomer compound represented by the formula In(Se^(n)Bu)₃ wassynthesized using the following procedure.

To a 500-mL round bottom Schlenk flask in an inert atmosphere glove boxwas added InCl₃ (6.95 g, 31 mmol), NaSe^(n)Bu (15 g, 94 mmol), and THF(200 mL). The reaction mixture was transferred to a Schlenk line andstirred for 12 h. The volatiles were subsequently removed under reducedpressure. The remaining solid residue was dissolved in hot toluene andfiltered. The volatiles from the filtrate were removed under reducedpressure and the resulting solid was washed with pentane. The finalcolorless solid was dried under reduced pressure and isolated (15 g, 29mmol, 92% yield).

NMR: (1H; C6D6): 0.913 (t, J_(HH)=7.2Hz, 9H, CH3); 1.43 (m, 6H, —CH₂—);1.72 (m, 6H, —CH₂—); 2.90 (t, J_(HH)=7.2Hz, 6H, SeCH₂—).

Example 20 Thin Film CIS/CIGS/CGS Materials Made from PolymericPrecursors

Examples of thin film CIGS, CIS and CGS materials made from polymericprecursors having predetermined stoichiometry are shown in Table 3. Theexamples in Table 3 were made by coating an ink containing 15-20% (w/w)of the specified polymeric precursor in solvent onto a molybdenum-glasssubstrate, drying the coating, and converting and annealing to achieve athin film.

TABLE 3 Thin film CIGS, CIS and CGS materials made from polymericprecursors having predetermined stoichiometry Drying Conversion Method(layers) thickness (T° C.) (T° C.) Annealing Ink %; Polymeric Precursor(min) (h) (T° C.) (h) Solvent spin coat (10) 700 nm 110 260 400 C., 1 h;p-xylene 20% [Cu_(1.0)In_(1.0)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat(10) 700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(0.8)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.8)]_(n) 15 1 650 C. 1 h spin coat(10) 700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) 15 1 650 C. 1 h spin coat(10) 700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.85)]_(n) 15 1 650 C. 1 h spincoat (10) 700 nm 110 260 400 C., 1 h; 6 p-xylene 20%[Cu_(1.0)In_(0.8)Ga_(0.2)(Se^(s)Bu)₄]_(n) 15 1 50 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.6)Ga_(0.4)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)Ga_(1.0)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10) 700 nm110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.1)Ga_(0.9)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.3)Ga_(0.7)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h rod coat (5)300 nm r.t. 200 C., l h; 400 C., 1 h THF 20%[Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)₄]_(n) 1-2 260 C., 15 min spin coat(10) 700 nm 110 260 400 C., 1 h p-xylene 20%[Cu_(1.0)In_(1.0)(Se^(s)Bu)₄]_(n) 15 1 spin coat (10) 700 nm 110 260 400C., 1 h p-xylene 20% [Cu_(0.8)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.8)]_(n) 15 1spin coat (10) 700 nm 110 260 400 C., 1 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) 15 1 spin coat (10) 700nm 110 260 400 C., 1 h p-xylene 20%[Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.85)]_(n) 15 1 spin coat (10) 700nm 110 260 400 C., 1 h p-xylene 20%[Cu_(1.0)In_(0.8)Ga_(0.2)(Se^(s)Bu)₄]_(n) 15 1 spin coat (10) 700 nm 110260 400 C., 1 h p-xylene 20% [Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(s)Bu)₄]_(n)15 1 spin coat (10) 700 nm 110 260 400 C., 1 h p-xylene 20%[Cu_(1.0)In_(0.6)Ga_(0.4)(Se^(s)Bu)₄]_(n) 15 1 spin coat (10) 700 nm 110260 400 C., 1 h p-xylene 20% [Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)₄]_(n)15 1 spin coat (10) 700 nm 110 260 400 C., 1 h p-xylene 20%[Cu_(1.0)Ga_(1.0)(Se^(s)Bu)₄]_(n) 15 1 spin coat (10) 700 nm 110 260 400C., 1 h p-xylene 20% [Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(s)Bu)₄]_(n) 15 1 spincoat (10) 700 nm 110 260 400 C., 1 h p-xylene 20%[Cu_(1.0)In_(0.1)Ga_(0.9)(Se^(s)Bu)₄]_(n) 15 1 spin coat (10) 700 nm 110260 400 C., 1 h p-xylene 20% [Cu_(1.0)In_(0.3)Ga_(0.7)(Se^(s)Bu)₄]_(n)15 1 spin coat (15) 1200 nm r.t. 300 C., 550 C., 1 hr p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 min spincoat (10) 800 nm r.t. 300 C., 550 C., 1 hr p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 min rodcoat (10) 700 nm r.t. 300 C., 550 C., 1 h THF 20%[Cu_(1.0)In_(1.0)(Se^(n)Hex)₄]_(n) 1-2 flash rod coat (10) 700 nm r.t.300 C., 550 C., 1 h THF 20% [Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(n)Hex)₄]_(n)1-2 flash rod coat (10) 700 nm r.t. 300 C., 550 C., 1 h THF 20%[Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(n)Hex)₄]_(n) 1-2 flash rod coat (10) 700nm r.t. 300 C., 550 C., 1 h THF 20%[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(n)Hex)₄]_(n) 1-2 flash spin coat (9) 500nm r.t. 300 C., 500 C. 2 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 every 3rdcoat min spin coat (11) 700 nm r.t. 300 C., 500 C. 2 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 every 3rdcoat min spin coat (12) 700 nm r.t. 300 C., 500 C. 2 h 3/6/9, p-xylene20% [Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 550 3 h12th coat min spin coat (12) 700 nm r.t. 300 C., 500 C. 2 h 3/6/9,p-xylene 20% [Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash30 550 3 h 12th coat, min 600 8 h spin coat (5) 300 nm r.t. 300 C., 550C., 1 h p-xylene 20% [Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2flash 30 min spin coat (10) 600 nm r.t. 300 C., 550 C., 1 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 min spincoat (15) 1000 nm r.t. 300 C., 550 C., 1 h 10th , p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 550 C. 1 h15th min spin coat (15) 1100 nm r.t. 300 C., none p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.9)]_(n) 1-2 flash 30min spin coat (15) 1100 nm r.t. 300 C., 400 C., 1 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.9)]_(n) 1-2 flash 30min spin coat (15) 1000 nm r.t. 300 C., 550 C., lh p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.9)]_(n) 1-2 flash 30min spin coat (10) 700 nm r.t. 300 C., none decane 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.9)]_(n) 1-2 flash 30min spin coat (15) 950 nm r.t. 300 C., 400 C., 1 h decane 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.9)]_(n) 1-2 flash 30min spin coat (15) 950 nm r.t. 300 C., 550 C., 1 h decane 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.9)]_(n) 1-2 flash 30min rod coat (8) 500 nm r. t. 300 C., 550 C., 1 h THF add.NaIn(Se-secBu)4 1-2 flash 10 15%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) min spin coat (10) 700 nm110 260 C., 1 h 650 C., 4 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) 15 spin coat (10) 700 nm110 260 C., 1 h 400 C., 1 h, 650 C. p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) 15 2 h, 650 C., 4 h spincoat (10) 700 nm 110 260 C., 1 h 650 C., 4 h, 650 p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) 15 C., 4 h knife coat(10) 1000 nm r.t. 300 C., 550 C., 1 h c-C₆H₁₂ 27%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 10 C₇H₁₆ minknife coat (10) 1000 nm r.t. 300 C., 550 C., 1 h 5th c-C₆H₁₂ 25%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.9)]_(n) 1-2 flash 10550 C., 1 h 10th C₇H₁₆ min

Example 21 Examples of Controlling the Stoichiometry of Materials

FIG. 17 shows results of methods for stoichiometric control of thecomposition of a polymeric precursor embodiment (MPP) of this invention.The x-axis refers to the weight percent of a particular atom, either Cu,In or Ga, in the monomer compounds used to prepare the polymericprecursor. The y-axis refers to the weight percent of a particular atomin the precursor compounds as synthesized, as determined by the use ofICP. The straight line correlation observed in FIG. 17 for differentpolymeric precursor compounds shows that the stoichiometry of thepolymeric precursor can be precisely controlled by the quantities of themonomers used to make the polymeric precursors. The straight linecorrelation observed in FIG. 17 also shows that methods of thisdisclosure can be used to make precursor compounds of any arbitrarydesired stoichiometry.

Example 22 Preparation of CIGS materials

A CIGS material was prepared from a polymeric precursor as follows. Asample of the polymeric precursor {(Cu)(Se^(t)Bu)(Se^(n)Bu)(0.75 In,0.25Ga)(Se^(n)Bu)₂} (40-60 mg) was initially heated from 20° C. to 260° C.over a period of about 1.5 h in an inert atmosphere (nitrogen). Thesample was allowed to cool to room temperature before a second heatingsequence was performed in which the sample was heated at 10° C./min from20° C. to 250° C., followed by heating at 2° C./min to 400° C. Theresulting CIGS material was cooled to 20° C. over a period of about 1 h.

Example 23

A CIGS material was prepared from a polymeric precursor as follows. Asample of the polymeric precursor {(0.85 Cu)(Se^(t)Bu)(Se^(n)Bu)(0.7In,0.3 Ga)(Se^(n)Bu)₂} (40-60 mg) was initially heated from 20° C. to260° C. over a period of about 1.5 h in an inert atmosphere (nitrogen).The sample was allowed to cool to room temperature before a secondheating sequence was performed in which the sample was heated at 10°C./min from 20° C. to 250° C., followed by heating at 2° C./min to 400°C. The resulting CIGS material was cooled to 20° C. over a period ofabout 1 h.

The X-ray diffraction pattern of this material is shown in FIG. 18. TheX-ray diffraction pattern of FIG. 18 showed the presence of a singlecrystalline CIGS phase, namely a tetragonal chalcopyrite phase.

Example 24

An analysis by X-ray diffraction of the structure of the crystallinephase of CIGS materials made with various polymeric precursors is shownin FIG. 19. The results in FIG. 19 showed that the degree ofincorporation of indium and gallium in the crystals of CIGS materialscan be detected by the relative position of the 2-theta-(112) peak ofthe X-ray diffraction pattern. As shown in FIG. 19, for crystals of CIGSmaterials a linear correlation was found between the percent indium ofthe precursor and the position of the 2-theta-(112) peak over a range ofpercent indium from about 30% to about 90%, where percent indium is100*In/(In +Ga). The CIGS materials were each made from a polymericprecursor having the corresponding percent indium. Thus, the resultsshowed that the stoichiometry of a CIGS material can be preciselycontrolled by the structure of the polymeric precursor used for itspreparation.

Example 25

FIG. 20 shows an analysis by Dynamic Light Scattering at 25° C. of themolecular weight of three polymeric precursors of this disclosure. Thepolymeric precursors were made from the chain-forming reaction ofmonomers of A, providing repeat units {M^(A)(ER)₂}, and monomers of B,providing repeat units {M^(B)(ER)₂}. Polymer 1 is{(Cu_(0.85))(Se^(t)Bu)_(0.85)(Se^(n)Bu)(In_(0.7)Ga_(0.3))(Se^(n)Bu)₂}and has a molecular weight estimated by DLS to be 17 kDa. Polymer 2 is{Cu(Se^(t)Bu)(Se^(n)Bu)(In_(0.7)Ga_(0.3))(Se^(n)Bu)₂} and has amolecular weight estimated by DLS to be 87 kDa. Polymer 3 is{Cu(Se^(t)Bu)(Se^(n)Bu)(In_(0.75)Ga_(0.25))(Se^(n)Bu)₂} and has amolecular weight estimated by DLS to be 59 kDa. The DLS data of FIG. 20show that the polymeric precursors of this disclosure are polymershaving molecular weights that can vary over a wide range.

Example 26

A CIGS material was prepared from a polymeric precursor as follows. Asample of the polymeric precursor{(^(n)BuSe)₂In_(0.3)Ga_(0.7)(Se^(n)Bu)(Se^(t)Bu)Cu} (40-60 mg) (Example11) was initially heated from 20° C. to 260° C. over a period of about1.5 h in an inert atmosphere (nitrogen). The sample was allowed to coolto room temperature before a second heating sequence was performed inwhich the sample was heated at 10° C./min from 20° C. to 250° C.,followed by heating at 2° C./min to 400° C. The resulting CIGS materialwas cooled to 20° C. over a period of about 1 h.

Example 27

A CIGS material was prepared from a polymeric precursor as follows. Asample of the polymeric precursor{(^(n)BuSe)₂In_(0.5)Ga_(0.5)(Se^(n)Bu)(Se^(t)Bu)Cu} (40-60 mg) (Example12) was initially heated from 20° C. to 260° C. over a period of about1.5 h in an inert atmosphere (nitrogen). The sample was allowed to coolto room temperature before a second heating sequence was performed inwhich the sample was heated at 10° C./min from 20° C. to 250° C.,followed by heating at 2° C./min to 400° C. The resulting CIGS materialwas cooled to 20° C. over a period of about 1 h.

Example 28

A CIGS material was prepared from a polymeric precursor as follows. Asample of the polymeric precursor{(^(n)BuSe)₂In_(0.7)Ga_(0.3)(Se^(n)Bu)(Se^(t)Bu)Cu} (40-60 mg) (Example13) was initially heated from 20° C. to 260° C. over a period of about1.5 h in an inert atmosphere (nitrogen). The sample was allowed to coolto room temperature before a second heating sequence was performed inwhich the sample was heated at 10° C./min from 20° C. to 250° C.,followed by heating at 2° C./min to 400° C. The resulting CIGS materialwas cooled to 20° C. over a period of about 1 h.

Example 29

A CIGS material was prepared from a polymeric precursor as follows. Asample of the polymeric precursor{(^(n)BuSe)₂In_(0.9)Ga_(0.1)(Se^(n)Bu)(Se^(t)Bu)Cu} (40-60 mg) (Example15) was initially heated from 20° C. to 260° C. over a period of about1.5 h in an inert atmosphere (nitrogen). The sample was allowed to coolto room temperature before a second heating sequence was performed inwhich the sample was heated at 10° C./min from 20° C. to 250° C.,followed by heating at 2° C./min to 400° C. The resulting CIGS materialwas cooled to 20° C. over a period of about 1 h.

1. A method for making a photovoltaic absorber material, the methodcomprising: providing a substrate; depositing onto the substrate an inkcomprising one or more compounds having the formula M^(B)(ER)₃ whereinM^(B) is In, Ga or Al, E is S or Se, and R is selected from alkyl, aryl,heteroaryl, alkenyl, amido, and silyl; heating the substrate.
 2. Themethod of claim 1, further comprising depositing a polymeric precursorcompound onto the substrate.
 3. The method of claim 2, wherein thepolymeric precursor compound is a CIGS, CIS or CGS precursor compound.4. The method of claim 1, wherein M^(B) is In or Ga, E is Se, and R isalkyl.
 5. The method of claim 1, wherein R is (C1)alkyl, (C2)alkyl,(C3)alkyl, (C4)alkyl, (C5)alkyl, or (C6)alkyl.
 6. The method of claim 1,wherein M^(B)(ER)₃ is In(SeR)₃, wherein R is alkyl.
 7. The method ofclaim 1, wherein M^(B)(ER)₃ is Ga(SeR)₃, wherein R is alkyl.
 8. Themethod of claim 1, wherein M^(B)(ER)₃ is In(SeR)₃, wherein R isn-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl,and mixtures thereof.
 9. The method of claim 1, wherein M^(B)(ER)₃ isGa(SeR)₃, wherein R is n-propyl, isopropyl, n-butyl, isobutyl,sec-butyl, t-butyl, n-pentyl, and mixtures thereof.
 10. The method ofclaim 1, wherein M^(B)(ER)₃ is In(Se^(sec)Bu)₃, In(S^(t)Bu)₃,In(Se^(n)Bu)₃, Ga(Se^(sec)Bu)₃, Ga(Se^(t)Bu)₃, Ga(SEt)₃, Ga(S^(t)Bu)₃,or Ga(Se^(n)Bu)₃.
 11. The method of claim 1, wherein the ink is asolution of the compounds in an organic carrier.
 12. The method of claim11, wherein the carrier is selected from aliphatic hydrocarbons,aromatic hydrocarbons, pentane, hexane, heptane, octane, isooctane,decane, cyclohexane, p-xylene, m-xylene, o-xylene, benzene, toluene,xylene, ethers, diethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran,siloxanes, cyclosiloxanes, silicone fluids, acetonitrile, esters,acetates, ethyl acetate, butyl acetate, acrylates, isobornyl acrylate,ketones, acetone, methyl ethyl ketone, cyclohexanone, cyclopentanone,lactams, N-methylpyrrolidone, N-(2-hydroxyethyl)-pyrrolidone, cyclicacetals, cyclic ketals, aldehydes, alcohol, methanol, ethanol, isopropylalcohol, thiols, butanol, butanediol, glycerols, alkoxyalcohols,glycols, 1-methoxy-2-propanol, acetone, ethylene glycol, propyleneglycol, propylene glycol laurate, ethylene glycol ethers, diethyleneglycol, triethylene glycol monobutylether, propylene glycolmonomethylether, 1,2-hexanediol, and mixtures thereof.
 13. The method ofclaim 1, further comprising a dopant, or an alkali dopant, or a compoundhaving the formula M^(alk)M^(B)(ER)₄ or M^(alk)(ER), wherein M^(alk) isLi, Na, or K, M^(B) is In, Ga, or Al, E is S or Se, and R is alkyl oraryl.
 14. The method of claim 1, further comprising one or morecomponents selected from the group of a surfactant, a dispersant, anemulsifier, an anti-foaming agent, a dryer, a filler, a resin binder, athickener, a viscosity modifier, an anti-oxidant, a flow agent, aplasticizer, a conductivity agent, a crystallization promoter, anextender, a film conditioner, and an adhesion promoter.